Added pygments to the test requirements
Fix bootstrap less to work with lessc >1.4

The old (~".${variable}") syntax was deprecated in 1.31 and removed in the
current version 1.4.

Bootstrap upstream already fixed this, but I think that this change has a lower
risk than completely putting in the latest bootstrap version for now.

I also regenerated the bootstrap css with lessc 1.4
Increased the bottom margin of .box'es.

The deletions from the css seem to be duplicated code generated by old lessc
versions.
Added a 10px margin between the direct children of .box .box-buttons-bottom

I had to use !important to override the rules like .box .box-buttons-bottom a.
This should probably be refactored to remove the !important.
Merge pull request #2 from voidus/master

Some less fixes, pygments in test-requirements.