per feedback, use reverse() when generating callback urls. Also generate thumbnails when ingesting static images. We'll need these handy for the CMS UI.

Support asset library references in CapaModule. Also some code refactoring/cleanup. Preparing for review and submit

Feature/cale/fix html module editing

Remove vestigial js include

Fix display of email address on 404 pages

Correct Terms of Use and Privacy static pages

Update Terms of Use and Privacy static pages

improvements in symbolic math checking.

Merging now because it is needed for Physics courses.

Fix news and announcements icons on the frontpage

Feature/cale/cms save validation

Load modules from the mongo modulestore as errordescriptors if creating a regular descriptor fails, but leave the location the same

Make imports into the CMS ignore broken modules, while still loading bad xml as error modules in the LMS

Make ErrorDescriptor continue to use the interface for __init__ that XModuleDescriptor uses, while providing a helper function for constructing from a different set of arguments

Move common code for updating modules in mongo to a single helper function that also handles creating the item if it doesn't already exist

Elseview press release