Patch 7.2.0/API changes

==New==
* New AddOns: Blizzard_APIDocumentation, , Blizzard_Deprecated
* New widget: MaskTexture
* New widget method: 
* New mixins: ObjectPoolMixin, Vector2DMixin, Vector3DMixin
==Changes==
* All equipment set related API have been moved to the new table. The old API will still be available via Lua versions implemented in Blizzard_Deprecated.
==Removals==
* Voice chat (later replaced with )
* Mac movie recording
==References==