Changes

Unreleased

The dvr tool can now invoke standalone scripts: dvr foo searches for dvr-foo in the system PATH.
Log entries can now be viewed with dvr log (depends on dateparser).
The dvr neigh command is now dvr discover.
ControlMessage and ControlRequest are now simply Message and Request, as there is no other kind of message or request.
The search module is now named files, and so is the corresponding DVRIPClient method.
The dateparser and humanize dependencies are now only required when the corresponding command-line options are used.

DVRs on the current network can now be listed with dvr neigh. This command does not require a hostname.
For all other commands, which do require a hostname, it should now be passed using the -h option to dvr.
Live video from camera N can now be obtained by passing monitor:N to dvr cat. Append ;hd or ;sd to select the corresponding stream, and mind the shell quoting.
Sizes are now displayed in GNU 'human-readable' format (2K, 31M, etc.) using humanize when dvr find is given the -h flag.

Files can now be listed with dvr find (depends on dateparser) and downloaded (to standard output) with dvr cat.
Device can now be rebooted with dvr reboot.
System time can now be set using dvr time (depends on dateparser).
The dvr info tool reports system time alongside uptime.
Connection classes are now in dvrip.io.
The test_connect development script is renamed to dvrip_test.
The dvr tool can now be launched under Windows.
Broken dependency on Python 3.7 and broken development dependencies on mock and typing_extensions are fixed.