Core/Chat: Refactored building chat packets

* Moved everything into one specialized method instead of being scattered all over the place
* Allow localizing creature names in chat messages (when using $N)
* Send SMSG_GM_MESSAGECHAT for gm messages
Merge branch 'master' into 4.3.4

Conflicts:
	src/server/game/Battlefield/Battlefield.cpp
	src/server/game/Battlegrounds/Battleground.cpp
	src/server/game/Chat/Chat.cpp
	src/server/game/Chat/Chat.h
	src/server/game/Entities/Object/Object.cpp
	src/server/game/Entities/Player/Player.cpp
	src/server/game/Entities/Player/Player.h
	src/server/game/Handlers/ChatHandler.cpp
	src/server/game/Texts/CreatureTextMgr.cpp
	src/server/scripts/Commands/cs_wp.cpp
	src/server/scripts/EasternKingdoms/ZulAman/boss_halazzi.cpp
	src/server/scripts/EasternKingdoms/ZulAman/boss_hexlord.cpp
	src/server/scripts/EasternKingdoms/ZulAman/boss_nalorakk.cpp
	src/server/scripts/EasternKingdoms/ZulGurub/boss_arlokk.cpp
	src/server/scripts/EasternKingdoms/ZulGurub/boss_mandokir.cpp
	src/server/scripts/EasternKingdoms/zone_arathi_highlands.cpp
	src/server/scripts/EasternKingdoms/zone_hinterlands.cpp
	src/server/scripts/EasternKingdoms/zone_silverpine_forest.cpp
	src/server/scripts/EasternKingdoms/zone_swamp_of_sorrows.cpp
	src/server/scripts/Kalimdor/CavernsOfTime/BattleForMountHyjal/instance_hyjal.cpp
	src/server/scripts/Kalimdor/zone_azshara.cpp
	src/server/scripts/Kalimdor/zone_darkshore.cpp
	src/server/scripts/Kalimdor/zone_durotar.cpp
	src/server/scripts/Kalimdor/zone_moonglade.cpp
	src/server/scripts/Kalimdor/zone_thousand_needles.cpp
	src/server/scripts/Kalimdor/zone_ungoro_crater.cpp