Add a "create_or_update_user" function to hu_pin plugin, and have all places that create a user use it.  The "pin3_create_user" filter function now passes along API data to the aforementioned function.  pin3 authenticate function has been simplified to use the new filter.  Make "add_groups_to_blog" function in permission plugin into a filter that's used by xmlrpc create blog method.  Add an endpoint for xmlrpc and expose a new "create_blog" function for LTI, as well as the built-in "get_blog_details" function.
Add plugin that tracks course blogs at point of creation and deletion.  Plugin creates a table on the WP side that maps an external course id to a unique blog.  Add xmlrpc method that calls upon the plugin to get all blogs associated with a course.
Add xmlrpc method to create a feed of posts/pages using built-in method that queries post table.
Merge branch 'develop' into staging