Bug#775483: hexen: verify that the demo works in some packaged engine, and re-enable

[Alexandre Detiste]

> Alright. I have filed a bug against chocolate-doom with g-d-p in CC that
> will get closed when the next chocolate-doom release is uploaded. So you
> will get informed that the Hexen demo is now supported.

Thanks,

I guess that calls for a new GDP release.

I noticed doomsday-compat doesn't check "$0" at all
so running "heretic" or "hexen" from command line doesn't work.
(the .desktop files generated by GDP are ok though).

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=789882

Alexandre