Fix chevron animation in publish button

Closes #4104

- Fixed the broken spiny animation used in the publish button
Merge pull request #4117 from PaulAdamDavis/fix-post-state-arrow

Fix chevron animation in publish button
Undisable nProgress

Closes #4095

* Removes the line that killed nProgress for PSM
* adds to styles to make nProgress appear again (ht @halfdan)

IRC: http://107.20.237.151:8081/logs/%23ghost/20140922#pm51214