[WIP] Moving from Prototype to jQuery

In reference with #1067.

I continue the changes introduced by @m-bodmer's PR.

## Changes Made

Added jQuery, jQuery UI and jQuery DataTable files
Change MarkUs login page to use jQuery
Change Dialog boxes to use jQuery
Change user role switch to use jQuery
Change auto update for submissions collected in the assignments dashboard
Removed a handful of RJS files and replaced with jQuery equivalents
Made minimal changes to backend to support jQuery AJAX calls
Added jQuery browser detection

## Future changes now made possible

Can switch over from Prototype FilterTable to jQuery DataTables for rendering tables
Can switch over more dialog boxes to use jQuery and jQuery UI for wider browser support [WIP]
Can complete a full migration from Prototype to jQuery before upgrading to a Rails version where jQuery becomes the default [WIP].

## Updated

Created a jQuery dialog factory
Migration from Prototype to jQuery made entirely for folders:
 - `admins/`
 - `annotation_categories/`