Blender Git Loki

Bake-API: Set Custom Cage to be Cage Object

Suggestion by Andy Davies (metalliandy) to conform with industry standard (custom cage is something else apparently)

Note: this is the last bake related commit I plan for 2.71/rc (unless
everyone agrees that we could squeeze in D546 - custom UVs, which would
be really nice to add for 2.71 scripters)

Note 2: I'll update the wiki docs shortly