Issue title: Customisable front-page blocks
 Issue body: Ushahidi V2 had blocks of content that could be added to the front page. 

Copied from V2 feature request 629: 

Ideas:
1. Video block pulling in from our YouTube, Vimeo accounts.
2. Photo block pulling in from Flickr by album, tag, etc.
3. Incoming SMS block; almost like twitter feed but isolated to just cell phone SMS

*Created by bodacea on 2014-08-09 02:19:26.*

*Imported from https://phabricator.ushahidi.com/T581*
 Comments: 
 Comment 0: *Comment by shadowhand on 2014-10-28 02:53:46:*

not sure this is actionable, leaving on the wishlist for now.
 Comment 1: *Comment by shadowhand on 2014-10-28 02:54:05:*

None
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