Replace Sprite-Icons with FontAwesome

Summary: The removes the sprite sheet 'icons' and replaces it with FontAwesome fonts.

Test Plan:
- Grep for SPRITE_ICONS and replace
- Grep for sprite-icons and replace
- Grep for PhabricatorActionList and choose all new icons
- Grep for Crumbs and fix icons
- Test/Replace PHUIList Icon support
- Test/Replace ObjectList Icon support (foot, epoch, etc)
- Browse as many pages as I could get to
- Remove sprite-icons and move remarkup to own sheet
- Review this diff in Differential

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: epriestley, Korvin, hach-que

Differential Revision: https://secure.phabricator.com/D9052

src/applications/diffusion/controller/DiffusionRepositoryListController.php

@@ -48,7 +48,7 @@ final class DiffusionRepositoryListController extends DiffusionController {
         ->setName(pht('New Repository'))
         ->setHref($this->getApplicationURI('new/'))
         ->setDisabled(!$can_create)
-        ->setIcon('create'));
+        ->setIcon('fa-plus-square'));
 
     return $crumbs;
   }