Comment box tabs don't match styling across GitLab
The tabs on a comment/description box don't match the styling we have throughout GitLab.
Current:
![Screen_Shot_2016-11-28_at_10.17.32_AM](data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==)
I propose we change the active, hover, and focus states of these tabs to match the new states for the navigation tabs:
![Screen_Recording_2016-11-28_at_09.21_AM](data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==)