Update style of snippets pages

![Screen_Shot_2015-10-18_at_13.04.13](/uploads/95d58b64fa81aa4e75568d2d7b4a6b08/Screen_Shot_2015-10-18_at_13.04.13.png)

![Screen_Shot_2015-10-21_at_11.11.10](/uploads/106371d718a07a9ccdad9148812211fd/Screen_Shot_2015-10-21_at_11.11.10.png)

Replaces !1567.

Fixes #1767 and #2538.


See merge request !1637