Changed device types to platforms and form factors

Bugs 969242, 969243, 978150, 978160, 978210

This patch updates the submit flow, devhub, reviewer tools, and the API to change device types to platforms and form_factors.

![screenshot 2014-03-19 15 04 30](https://f.cloud.github.com/assets/1106/2466633/92ac9584-afb2-11e3-97a0-ed334a64bc9f.png)

A follow-up patch will remove the database table and Elasticsearch field and update fireplace to send the new parameters.
:+1: