Enable tests modules to auto-import all test files in their directories.
simpler user experience for registration; now no recurring refresh, window to close--just a callback url.
central-server-side of redirect.  This also forces the sync to run, with no confusion to see that the device has not yet sent sync data to the central server.
Merge branch 'redirect_to_force_sync' of github.com:bcipolli/ka-lite into redirect_to_force_sync

Conflicts:
	kalite/securesync/views.py
Merge branch 'develop' of github.com:learningequality/ka-lite into redirect_to_force_sync
__unicode__ function must use u'' format strings (see registration app for an example like these changes.
adding tests
making __unicode__ work on unsaved objects; gracefully failing sign() on unsaved objects
unicode tests for main objects
Merge branch 'develop' of github.com:learningequality/ka-lite into __unicode__support

Conflicts:
	kalite/contact/tests/__init__.py
updating error logic in coach reports; adding tests to verify if-then-else logic.
better documentation and code structure, based on self-code review
cleaning missing topics.  Hard problem
fixing bug in looping over children, recovered one missing child.
Merge branch 'coach_reports_error_message' into empty_subtopics_1
add tests for checking that knowledge map elements are on the page (though does not confirm that they are visible.
making change to solve server error, adding regression test case.
made get_uuid assert good values, rather than full_clean; modularized test code
wrap all API calls with error catching, so all API return Json-based errors
update video_download