Implement twitter bootstrap

This PR includes a major overhaul of the frontend to reorganize things and implement the Twitter bootstrap framework (both CSS and JS).  As we start to add sections to the site (namely administration screens), bootstrap will help us quickly achieve a nice look and feel.  Did our best to keep the user-facing pages true to the Selfstarter aesthetic.

-The "Preorder" controller and views were renamed and reorganized into "Project", as this is a more appropriate (and generalized) descriptor for these sections of the site (homepage, checkout, etc)
-Twitter bootstrap was implemented using the Bootstrap-Sass gem
-HTML and CSS were reworked a bit to accommodate for bootstrap