Home twitter module

This branch makes the following changes to the homepage:
* Adds a twitter feed 
* Moves the "Most Popular" module down
* Removes the AudioVision section
* Adds a twitter time format extension to moment.js
* Modifies smart_time.js to use the moment.js twitter extension


Note:
The tweet creation and caching of the homepage twitter works exactly like the KPCCForum tweets so all I did was create a new template and add new args to the TwitterCache rake task. 
See line 185 https://github.com/SCPR/SCPRv4/compare/home-twitter-module#diff-cbaf3c10182855f3c1725b82670d7fb1R185

Should there be a 'cleaner' way to do this aside from looping over the array of args? Since we won't be creating a lot of these twitter feeds I thought this was okay.