doc: Add a .desktop and .appdata.xml file for Cockpit

[hughsie]

This allows the user to launch Cockpit from the shell and also makes it visible
to be installed in GNOME Software.

IMPORTANT: This is not anyware good enough for merging, but we can work through the FIXMEs if this is a feature you guys actually want. :)

[stefwalter]

Seems like something we could merge. Installation via GNOME software isn't a primary use case, but I think it's not a bad idea.

By the way, make distcheck fails:

  ITMRG  doc/cockpit.appdata.xml
Cannot open doc/cockpit.appdata.xml: No such file or directory
make[3]: *** [doc/cockpit.appdata.xml] Error 2
make[3]: Leaving directory `/home/travis/build/cockpit-project/cockpit/cockpit-0.19/_build'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/home/travis/build/cockpit-project/cockpit/cockpit-0.19/_build'
make[1]: *** [all] Error 2
make[1]: Leaving directory `/home/travis/build/cockpit-project/cockpit/cockpit-0.19/_build'
make: *** [distcheck] Error 1

[stefwalter]

This would be the icon from http://cockpit-project.org/

[hughsie]

Okay, thanks. I wonder if in the meantime Andreas could do 3-5 official screenshots of the latest code and put them up on the website somewhere? I've fixed the URL, done a 64px icon, and fixed make distcheck.

[stefwalter]

@andreasn do you have any 16:9 screenshots of cockpit?

[andreasn]

Will provide shortly!

[mvollmer]

One issue worth thinking about would be whether or not to open the firewall for the Cockpit port when people install Cockpit for local use.

If the description makes it clear that Cockpit is also accessible remotely by default, I think we should just open it, for simplicity.

[andreasn]

I hope I did the last one right

[hughsie]

Looks good to me, thanks! Stef, do you want to collapse this down to one commit manually and pull to master?

[mvollmer]

Continued in #1085.