Core/PacketIO: Corrected structures of SMSG_PARTY_MEMBER_STATS and SMSG_PARTY_MEMBER_STATS_FULL, fixes weird pet behavior in groups (appearing as "Unknown", breaking combat logs)

Closes #345
Core/Spells: Fixed a silly typo in SpellInfo::_IsPositiveEffect.

Fixes some auras being displayed as debuffs while they should not. (Just see Invisibility #66)

Ref. #7912
Core/Spells: Fix a logging message error
DB/Creatures: set immunities for some Raidbosses

Closes #4947
Closes #9674
Closes #9675
DB/Creatures: update creature_text for Forgemaster Garfrost and add visual aura

Closes #9720
Core/Players: Fixed tabard championing in normal modes of WotLK level 80 dungeons

Closes #9227
Merge remote-tracking branch 'origin/master'