Added ContentEntry.whatIsIt to determine if an embed code or URL can be added as a known type of content item
Moved JsonConverters to com.impressory.play.json prior to breaking it up
Moved JsonConverters into com.impressory.play.json package, and split it up

RecordedChatEvents are yet to be revised into this simpler way of doing JSON
Adjust ContentController.whatIsIt to return minimalist JSON for the ContentEntry not just the ContentItem

Also changes ContentEntry.kind to be a def (looking it up on the ContentItem) rather than a val
Added share form to the Newsfeed page

This allows adding content by pasting in the URL.

Still to be implemented: news posts (no item), tags, flags, and notifying open news feeds that new content has been added.
Modified the format of addContent submissions to more closely match JSON output of ContentEntry