Adding AJAX inbox update functionality. The inbox will now periodically update, reordering itself as necessary, inserting any new threads that have been updated since page load, as well as updating any threads that have changed since page load. The refresh time can be adjusted in the block settings.
Fixing bug preventing message form from updating when posting a message, and stifling email notifications.
#2857048: Create web test base case
#2856866: Identify and implement alter hooks
#2857782: Initialize ppr_styleguide submodule info and dependencies
#2853271: Add "No Reference" option to page status filter
#2852651: Styleguide Compliance
#2859041: Reorganize Web Test Cases