Fixing jqueryjs block; remove non-jquery script tags.
Tweaks for IE compatibility (HTML/JS fixes and added json2.js).
Removed unneeded div.
Merge branch 'css_cleanup' into ie_fixes
Merge branch 'release-0.10' into ie_fixes
Navigation bar now works in IE8.
Upgrading to video.js version 4, to get it working on IE.
Merge remote-tracking branch 'upstream/release-0.10' into ie_fixes
Use video.js 4 in IE, and video.js 3 in other browsers.
fixing bug where deleted video files did not invalidate their cache.  Also stop auto-generating cache files by default, as it's very slow and videoscan is called as a function for update page loading.

Conflicts:
	kalite/main/management/commands/videoscan.py
duplicating change in another branch

Conflicts:
	kalite/securesync/api_views.py
	kalite/utils/decorators.py
fixing two caching bugs, based on deletion.  Adding test logic for setting up temporary cache and content_root, so test scripts of caching and video manipulation can occur without touching any existing cache items or videos.

Conflicts:
	kalite/main/tests/__init__.py
set _web_cache on demand, to avoid errors when caching is disabled.
Merge branch 'release-0.10' into ie_fixes
Merge branch 'release-0.10' of github.com:learningequality/ka-lite into videoscan_caching_bug

Conflicts:
	kalite/securesync/api_views.py
Fixes to the nav bar to address code review.
Fixes to the main browser tests to get them all to pass again.
Merge branch 'release-0.10' into ie_fixes

Conflicts:
	kalite/templates/base_distributed.html
Merge branch 'ie_fixes' into browser_test_fixes

Conflicts:
	kalite/main/tests/browser_tests.py
Tweak to tests to get them working with ie_fixes.