Store and display user stats on page
Models and their usage refactoring. Resolves #34.

 - Updated all the models so that they reflect actual scheme
 - Renamed several fields in the models to match Python conventions
 - Updated most of the code to use mongoengine ORM
 - Changed tags get_or_create in "next" view to atomic update_one as
   the former is deprecated and considered unsafe
 - Improvements to admin
Merge pull request #40 from dchaplinsky/feature/models_update

Models and their usage refactoring. Resolves #34.
Merge with trunk
CR fixes
Merge pull request #39 from dchaplinsky/development

Store and display user stats on page
Fix for index on parallel arrays
#16: limit list of suggestions to base tags and tags created by current user
Merge pull request #41 from dchaplinsky/development

#16: limit list of suggestions to base tags and tags created by current ...
Added box to enter recognizable characters found on shred
remove useless space
CR Fixes
Merge pull request #42 from dchaplinsky/development

Merge with trunk
Modified tags input to disallow adding same tag over and over again
CR fixes
Merge pull request #43 from dchaplinsky/development

Modified tags input to disallow adding same tag over and over again
Shreds review page. Resolves #22.

 - Implemented a new page that contains current user's tagged shreds
 - Added a pagination macro
 - Moved nav to base.html with a block to extend
 - Next shred loading will only happen on the main page
 - Models now inherit flask-mongoengine's Document in order to obtain
   extended functionality
 - Small CSS fixes
Simplified the prev/next pagination a bit
Improvements for review page

 - Added current user's `recognizable_chars` to the shred item
 - Increased shreds per page to 100
 - Decreased the shred image to 40px for more info space
 - Layout and styling for the shred item
 - Review page now only accessible to authenitcated users
 - Renamed the review page nav item and decreased the brand font size
Merge pull request #44 from dchaplinsky/feature/review_page

Shreds review page. Resolves #22.