Fix appearance and interaction issues of the scope icon popovers

Those issues were introduced by the upgrade to bootstrap 3.2.0 and the
custom handlers that were added for the config file diff popovers.

Fixes #306
Use a monospace font for the config file diffs

Fixes #307
Merge pull request #310 from SUSE/review_141015_fix_popovers

[Review] Request from 'aduffeck' @ 'SUSE/machinery/review_141015_fix_popovers'