Scripts/Instance: The Stonecore updates

Stonecore Teleporters scripted. Some corrections, better handlings, fixed Travis warnings ...

Closes #13626

(cherry picked from commit 9a941ae125c8b22b802270f7f419c1a8bfd2a343)

Conflicts:
	src/server/scripts/Maelstrom/Stonecore/boss_high_priestess_azil.cpp
	src/server/scripts/Maelstrom/Stonecore/boss_ozruk.cpp
	src/server/scripts/Maelstrom/Stonecore/instance_stonecore.cpp
	src/server/scripts/Maelstrom/Stonecore/stonecore.cpp