Remove default mod

flare-engine now supports loading the default mod from either an
installed copy of flare-engine, or from a local folder like
`~/.local/share/flare/default/mods/`.
Merge remote-tracking branch 'upstream/master' into fixes
Splitting up credits for mods.
Merge pull request #320 from stefanbeller/credits

Splitting up credits for mods.
Merge pull request #313 from dorkster/fixes

Remove default mod