docs: line-wrap markdown and use double-spacing

Use two spaces to separate sentences to make the source easier to read
in monospace fonts (such as when editing or reviewing it), especially
for longer paragraphs.  The HTML output should still look the same.

Misc: This also removes source-level ambiguity regarding abbreviations
(such as "Mr.") vs the end of sentences and enables moving between
sentences in vi with `(` and `)`, for example.

.github/pull_request_template.md

@@ -7,7 +7,7 @@ following:
 - The ordering of options follow the rules described in
   [etc/templates/profile.template](../blob/master/etc/templates/profile.template)
   (/usr/share/doc/firejail/profile.template when installed).
-- Order the arguments of options alphabetically. You can easily do this with
+- Order the arguments of options alphabetically.  You can easily do this with
   [sort.py](../blob/master/contrib/sort.py).
 
   The path to it depends on your distro:

CONTRIBUTING.md

@@ -15,17 +15,18 @@ a comment in our dedicated issue:
 When submitting a bug report, please provide the following information so that
 we can handle the report more easily:
 
-- firejail version. If you're not sure, open a terminal and type `firejail --version`.
+- firejail version.  If you're not sure, open a terminal and type `firejail
+  --version`.
 - Linux distribution (so that we can try to reproduce it, if necessary).
-- If you know that the problem did not exist in an earlier version of firejail, please mention it.
-- If you are reporting that a program does not work with firejail, please also run firejail with
-  the `--noprofile` argument.
-  For example, if `firejail firefox` does not work, please also run `firejail --noprofile firefox` and
+- If you know that the problem did not exist in an earlier version of firejail,
+  please mention it.
+- If you are reporting that a program does not work with firejail, please also
+  run firejail with the `--noprofile` argument.  For example, if `firejail
+  firefox` does not work, please also run `firejail --noprofile firefox` and
   let us know if it runs correctly or not.
 - You may also try disabling various options provided in
   `/etc/firejail/<ProgramName.profile>` until you find out which one causes
-  problems.
-  It will significantly help in finding a solution for your issue.
+  problems.  It will significantly help in finding a solution for your issue.
 
 Please note: If you are running Debian, Ubuntu, Linux Mint, or another related
 distribution and you installed firejail from your distro's repositories, please

README

@@ -8,7 +8,7 @@ Clementine, Rhythmbox, Totem, Deluge, qBittorrent, DeaDBeeF, Dropbox, Empathy,
 FileZilla, IceCat, Thunderbird/Icedove, Pidgin, Quassel, and XChat.
 
 Firejail also expands the restricted shell facility found in bash by adding
-Linux namespace support. It supports sandboxing specific users upon login.
+Linux namespace support.  It supports sandboxing specific users upon login.
 
 Download: https://sourceforge.net/projects/firejail/files/
 Build and install: ./configure && make && sudo make install
@@ -28,7 +28,7 @@ Compile and install the mainline version from GitHub:
     cd firejail
     ./configure && make && sudo make install-strip
 
-On Debian/Ubuntu you will need to install git and gcc. AppArmor development
+On Debian/Ubuntu you will need to install git and gcc.  AppArmor development
 libraries and pkg-config are required when using the --enable-apparmor
 ./configure option:
 

README.md

@@ -5,20 +5,24 @@
 [![CodeQL CI](https://github.com/netblue30/firejail/workflows/CodeQL/badge.svg)](https://github.com/netblue30/firejail/actions?query=workflow%3ACodeQL)
 [![Packaging status (Repology)](https://repology.org/badge/tiny-repos/firejail.svg)](https://repology.org/project/firejail/versions)
 
-Firejail is a SUID sandbox program that reduces the risk of security breaches by restricting
-the running environment of untrusted applications using Linux namespaces, seccomp-bpf
-and Linux capabilities. It allows a process and all its descendants to have their own private
-view of the globally shared kernel resources, such as the network stack, process table, mount table.
-Firejail can work in a SELinux or AppArmor environment, and it is integrated with Linux Control Groups.
-
-Written in C with virtually no dependencies, the software runs on any Linux computer with a 3.x kernel
-version or newer. It can sandbox any type of processes: servers, graphical applications, and even
-user login sessions. The software includes sandbox profiles for a number of more common Linux programs,
+Firejail is a SUID sandbox program that reduces the risk of security breaches
+by restricting the running environment of untrusted applications using Linux
+namespaces, seccomp-bpf and Linux capabilities.  It allows a process and all
+its descendants to have their own private view of the globally shared kernel
+resources, such as the network stack, process table, mount table.  Firejail can
+work in a SELinux or AppArmor environment, and it is integrated with Linux
+Control Groups.
+
+Written in C with virtually no dependencies, the software runs on any Linux
+computer with a 3.x kernel version or newer.  It can sandbox any type of
+processes: servers, graphical applications, and even user login sessions.  The
+software includes sandbox profiles for a number of more common Linux programs,
 such as Mozilla Firefox, Chromium, VLC, Transmission etc.
 
-The sandbox is lightweight, the overhead is low. There are no complicated configuration files to edit,
-no socket connections open, no daemons running in the background. All security features are
-implemented directly in Linux kernel and available on any Linux computer.
+The sandbox is lightweight, the overhead is low.  There are no complicated
+configuration files to edit, no socket connections open, no daemons running in
+the background.  All security features are implemented directly in Linux kernel
+and available on any Linux computer.
 
 ## Videos
 
@@ -103,7 +107,7 @@ See also <https://wiki.ubuntu.com/SecurityTeam/FAQ>:
 > What software is supported by the Ubuntu Security team?
 >
 > Ubuntu is currently divided into four components: main, restricted, universe
-> and multiverse. All binary packages in main and restricted are supported by
+> and multiverse.  All binary packages in main and restricted are supported by
 > the Ubuntu Security team for the life of an Ubuntu release, while binary
 > packages in universe and multiverse are supported by the Ubuntu community.
 
@@ -147,7 +151,7 @@ cd firejail
 ./configure && make && sudo make install-strip
 ```
 
-On Debian/Ubuntu you will need to install git and gcc. AppArmor development
+On Debian/Ubuntu you will need to install git and gcc.  AppArmor development
 libraries and pkg-config are required when using the `--enable-apparmor`
 ./configure option:
 
@@ -171,7 +175,7 @@ firejail vlc                # starting VideoLAN Client
 sudo firejail /etc/init.d/nginx start
 ```
 
-Run `firejail --list` in a terminal to list all active sandboxes. Example:
+Run `firejail --list` in a terminal to list all active sandboxes.  Example:
 
 ```console
 $ firejail --list
@@ -191,16 +195,16 @@ firecfg --fix-sound
 sudo firecfg
 ```
 
-The first command solves some shared memory/PID namespace bugs in PulseAudio software prior to version 9.
-The second command integrates Firejail into your desktop. You would need to logout and login back to apply
-PulseAudio changes.
+The first command solves some shared memory/PID namespace bugs in PulseAudio
+software prior to version 9.  The second command integrates Firejail into your
+desktop.  You would need to logout and login back to apply PulseAudio changes.
 
 Start your programs the way you are used to: desktop manager menus, file
 manager, desktop launchers.
 
-The integration applies to any program supported by default by Firejail.
-There are over 900 default applications in the current Firejail version, and
-the number goes up with every new release.
+The integration applies to any program supported by default by Firejail.  There
+are over 900 default applications in the current Firejail version, and the
+number goes up with every new release.
 
 We keep the application list in
 [src/firecfg/firecfg.config](src/firecfg/firecfg.config)
@@ -290,8 +294,8 @@ Discussion:
 
 ### Profile Statistics
 
-A small tool to print profile statistics. Compile and install as usual.
-The tool is installed in the /usr/lib/firejail directory.
+A small tool to print profile statistics.  Compile and install as usual.  The
+tool is installed in the /usr/lib/firejail directory.
 
 Run it over the profiles in /etc/profiles: