Fix pylint violations in xmodule static_content.py

Clean tests step now removes stale coverage report files.

Ned/remove unused imports

Remove simplewiki from the codebase

Clean up pep8 E128 issues

Cale/create dev env fixes

Pep8 cleaning.

Jonahstanley/fix flakey tests

Added test cleaning to fasttest_* instead of test_*, so that
it always gets executed for lms and cms tests.

Added comment to `directory` command for tests.rake

Separated cleaning of test fixtures from cleaning of reports
directory to resolve conflicts with collectstatic.

Peter fogg/remove video xml

Don't mention edge in the e-mail; same text used for edge and edx.

studio - revising the visual design of UI well pattern

On marketing site, disable course settings options that do not work.

Added testing for grading settings

Conflicts:
	common/djangoapps/terrain/ui_helpers.py

As a result, changed inputfield to return the css, and all of the element.fill() to css_fill

Will/fix video acceptance tests