Issue/419

This branch allows adds an extra step to the install routine to clone the 'adapt_framework' repository from GitHub.  (Note that in future this could possibly move to a bower package instead)

For each tenant, a copy is made of this repository, and is used to dynamically compile the course, e.g. so that different themes can be used.  In future this could also be used to deliver customised installs.
here and on lines 356, 351 - you're going to have the callback invoked multiple times - this could lead to nasty bugs. there should only be a single invocation of the callback in the flow of execution.