Trying mongodb

Added MongoDB to Chef config and Gemfile. Added first Mongo model and
controller, create works.
Adding items with Mongo works

Able to add items to list and save in MongoDB. Response works with
Firehose
Live updating and selecting works with DB storage

Selecting an item will propagate to connected clients (not to DB to save
query time)

Updating an item's title will propagate to connected clients and DB
Working on order updating
modifying reodering code
Fixed reordering bug
Changed to Puma, fixed another reordering bug

Changed Rails webserver from Thin to Puma. Now getting better
performance. Changed Firehose server from Thin to Rainbows! (v4.4.3)

Fixed reordering issue where stale attrs would still be PATCHed to the
server.