Core/Command: Improve .group list to feature several notes and features to improve handling.
Core/Misc: Get rid of some useless code
Merge pull request #11050 from Ascathor/master

Core/Command: Improve .group list to feature several notes and features ...
DB/SAI: Misc Fixes from IT

By @dr-j and @untaught
Fixes #11081 fixes #11080 fixes #11082
Core/Quest: Remove assertion

Remove assertion about Quest ExclusiveGroup since they are triggered even when adding valid quests to npcs. Fixes #8336 .
How to reproduce steps:
- .gm off
- add quest 11335 in creature_queststarter
- .reload creature_queststarter
- get in range of that creature
- .gm on
- assertion triggered
Merge branch 'master' of https://github.com/TrinityCore/TrinityCore into teste2