Increased default thread pool size as it now handles more than signals and remote access
DB/Quests: Add conditions to quest The Symbol of Live

Closes #11444
Core/Authserver: Fixed changing realms
Core/Misc: Replace rand() calls with SFMT
DB/Schema: Change playercreateinfo_skills engine to MyISAM
Merge branch 'master' of https://github.com/TrinityCore/TrinityCore

Conflicts:
	src/server/scripts/Northrend/Naxxramas/boss_gluth.cpp