Ch 855

Making this PR against CH-845 as that was its starting point.

This adds some limited support for personalizable fields on field collections on other entities. 

The main limitation is that only one level of field collection is supported - nested field collections are not handled here.
Yes, every time I see them in the code I cringe too - I know that this is going to bite us and it's only a matter of time, but definitely beyond the scope of this story.