Core/SmartScripts: fix escort quest group-complete
Core/Quest: Allow money reward for quests to be modified.

Added a rate for both regular quest reward and for quest reward given on max level. Defaulted to 1.
Merge pull request #12893 from Ascathor/master

Core/Quest: Allow money reward to be modified.
Merge pull request #12877 from ShinDarth/tc_fix_escort_quest_group_complete

Core/SmartScripts: fix escort quest group-complete