Feature/cdodge/static tab edit

address feedback from cale

Conflicts:
	rakefile

Feature/ned/quieter tests

Put the coverage data files in the reports dir, where they will be treated like the disposable things they are.

Split out requirements that come from the local mitx repo and those that come from github, and upgrade the local requirements before running tests

fix up styling by reusing existing CSS class names. Also refactor some code regarding the management of static_tabs so that it's in the course as course contains references to static_tabs in the current data model

Feature/cale/js tests

Fix/cdodge/delete last component does not stick

Simple Pearson Testing

Add support for subtitle download link