add Q3Rally gamepack

Q3Rally gamepack, license currently unknown, I'll ask P3rlE

changed the description

Current gamepack contains an entities.def file that derivates from Quake3, hence being proprietary.

P3rlE said a new gamepack made from scratch is coming, this one will fix license issues.

added 8 commits

• 9ed8a9ea...bbbc73e1 - 7 commits from branch xonotic:master
• 706da85e - add Q3Rally gamepack

Compare with previous version

approved this merge request

I merge it to make it usable since now. A later commit will mark it as free when it will be free.

merged

mentioned in commit c1f506c4