Slideshow bugs

[brandonhundt]

How to reproduce:

1. Create slideshow in the body
2. Upload an image into the first slot
3. Switch to search for existing image and select an image
   When you add that image it doesn't confirm its been added, and when you go to save it gets into a loading loop.

Also, we are seeing a lot of slideshows in Manage Embeds that have images that were saved without data, either by the Add Image process not being completed by the user or from errors.

One possible reason may be because validation for the title/alt/license fields is missing (they are not currently required where image embeds require them).

[ethorne]

I currently have this fixed and tested - just dealing with one pesky issue that