Document all the ways to declare source and patch files

[oturpe]

In rpkg#725, there was a need to authoritative documentation of different ways to declare source and patch files in a specfile, but people involved could not find any. The natural place for this would be Spec file format, but it has only very basic description of Source and Patch. I tried looking at other pages as well, but still could not find anything.

Is your feature request related to a problem? Please describe.
rpkg#725

Describe the solution you'd like
In my opinion, a good description of Source and Patch would include, either in those sections or

1.Numbered SourceXX form
2. Unnumbered Source form
3. %sourcelist and %patchlist

Additionally, I could not find the statement that tags are parsed in case-insensitive manner in the spec file format page. It would be good to have that as well.

Describe alternatives you've considered
none

Additional context
none

[dmnks]

Additionally, I could not find the statement that tags are parsed in case-insensitive manner in the spec file format page. It would be good to have that as well.

I don't think case insensitivity is something we should promote/encourage as that would just make spec files less readable or consistent.

The other points are valid, though. Funnily enough, we never documented the %patchlist and %sourcelist sections, so that's certainly something we should fix.

Thanks for the report!