Scss cleanup

 (there really should be some convention for all gitlab css)

Fonts, variables and mixins are now all in their own stylesheets

can't open a chinese file name doc

Improve admin section

fix resque start

Projects count at dashboard

* layout: add 'Groups' item to main_menu
* admin/dashboard: add a ui-box for groups
* projects and groups: remove nav tabs

Add a link to each project on the Issues dashboard

if link to a chinese file name, it will jump to error page;
for example, the chinese file name called "消息文档.md", when after urlencode, it will be "%E6%B6%88%E6%81%AF%E6%96%87%E6%A1%A3.md", but after use History.pushState, will jump to a bad decode link. 

Fix code highlighting