Add am images_with_captions collection
Revert "Add am images_with_captions collection"

This reverts commit 2decf62704bd1d77f0eb553cc4b97aec6c87a42d.
Add an images_with_captions collection
Update doc to include images_with_captions
Correct code example for images_with_captions
Merge branch 'master' of https://github.com/anitagraham/refinerycms-page-images