Adds xblock handler_url support to the LMS, and makes handle_ajax use
that code.

[LMS-230] [LMS-229]

LTI blade allows to include LTI components to courses.
Python integration, Jasmine and acceptance tests are included.

LTI blade allows to include LTI components to courses.
Python integration, Jasmine and acceptance tests are included.

This reverts commit 2894b21c, reversing
changes made to 34d0fe15.

Now all Video tags and VideoAlpha tags will be handled by VideoAlpha.

Conflicts:
	common/static/coffee/src/logger.coffee

Conflicts:
	common/static/coffee/src/logger.coffee

This allows us to a) compile the coffeescript and sass from xmodules
using the new out-of-band method and b) reload xmodule static content
whenever it changes, which should make devs much happier.

  - ops view for the desktop app to talk to
  - xmodule that talks to the foldit model and displays the student's state
  - grading tweak to make grade updates from an external service work:
    - Add an always_recalculate_grades property to XModuleDescriptor.

first pass at static tab editing. Doesn't yet support drag/drop as well as new tab creation, which needs to modify the policy on the course

implement static tabs. rejigger .tar.gz import to do the re-namespacing as a post-processing step as we need to retain the original url_name during the import. Also, migrate the presentation tier to use module_render.py::get_module() to better unify HTML'ifying stuff

- Piotr requested this.  Hopefully it doesn't break anything, but we should run it by the content fellows before merging.