DB/SAI: Fix startup error

By untaught, closes #11587
Core/Spells: Fixed crash happening when a spell script set target to NULL in OnObjectTargetSelect hook for spells using nearby target selection
Core/Map: Save weather, light and music overrides in map to send them to players logging in
Core/Transports: Fixed crashes happening when a transport was despawned with players/dynamicobjects on it
Core/Spells: Fixed target selection hooks running twice for each effect if both target A and B were using the same hook type (OnObjectAreaTargetSelect, OnObjectTargetSelect, OnDestinationTargetSelect)
Scripts/ZulAman/Halazzi: convert text to create_text and fixed despawn of cat
Core/Transports: Enabled LoS on transports
Merge pull request #11763 from MitchesD/misc

Scripts/ZulAman/Halazzi: convert text to create_text and fixed despawn of cat
Scripts/Icecrown Citadel: Icecrown Gunship Battle
Fixed build without PCH
Merge branch 'master' of git://github.com/TrinityCore/TrinityCore

Conflicts:
	src/server/scripts/Northrend/IcecrownCitadel/boss_the_lich_king.cpp
	src/server/scripts/Northrend/IcecrownCitadel/icecrown_citadel.h
	src/server/scripts/Northrend/IcecrownCitadel/instance_icecrown_citadel.cpp
	src/server/scripts/Spells/spell_generic.cpp
Fix some errors