Added Users, User Activity and Reports tabs to User Tracking menu page
Fixed bug in displaying the device pixel ratio
Added some more settings to the General tab to turn on or off tracking AJAX calls, page loads and element selectors
Added Elements tab to the Settings menu page

git-svn-id: https://plugins.svn.wordpress.org/hotspots/trunk@778268 b8457f37-d9ea-0310-8a92-e5e31aec5664