Merge pull request #274 from modilabs/design_improvements

manifest caching is back, fix for repeats, upload input styling
fix #275 POST request to get preview url
Provide feedback to user when loading fails. For testing on dev server, issue #277
recompiled
added errors for duplicate meta node children
recompiled
Merge pull request #278 from modilabs/loaderrors

Loaderrors shown to user
Merge pull request #72 from modilabs/master

preview API fix + feedback to user when loading fails