Restyle the course overview page

Squashed commit of the following:

commit c332ab4fbca5e41ffb232c0cb96524f54d13a33f
Merge: e1d1c39 5588c7d
Author: Matt Buck <techpeace@gmail.com>
Date:   Tue Jun 24 23:39:14 2014 -0500

    Merge branch 'master' into restyle-course-overview

    Conflicts:
    	app/views/courses/show.html.slim

commit e1d1c39eb2b0e0e980f6d9befb6a4b9b2c07211e
Merge: 2f5e592 ea4e225
Author: Matt Buck <techpeace@gmail.com>
Date:   Tue Jun 24 23:39:14 2014 -0500

    Merge branch 'master' into restyle-course-overview

commit ea4e2251f9c25028244e6887d2ada853fda1e8e9
Author: Matt Buck <techpeace@gmail.com>
Date:   Tue Jun 24 23:39:14 2014 -0500

    Restyle course overview page

commit 2f5e592a18d23591aad1ce21f22e93261f187cb4
Author: Matt Buck <techpeace@gmail.com>
Date:   Sun Jul 20 17:25:20 2014 -0500

    finish up

commit 4ce2ef909cdfd117344087d635507cccbb21f47c
Author: Matt Buck <techpeace@gmail.com>
Date:   Sun Jul 20 15:51:24 2014 -0500

    Clean up the layout a bit

commit 0ef90615a0526b21ce4fe84c36a0d0a4ae120e7f
Author: Matt Buck <techpeace@gmail.com>
Date:   Sun Jul 20 15:23:10 2014 -0500

    Refactor to use Foundation tabs