Alert Improvements by Xon 2.14.0

• Fix typo in 'alert summarization' phrase

• Fix XF2.1 summarized/grouped alerts support

• Add missing phrase in XF2.1
• Load javascript required to make 'mark-unread' link work outside the alerts page.

• Remove use of get_lock which is unsupported in galera clustering, and causes errors in Percona XtraDB Cluster.

• Fix XF2.1 adding options to account preferences page

• Support for upcoming Report Improvements for XF2 add-on
• Support for XF2.1 and XF2.0

• Support Content Rating 1.3.x
  • Requires minimum version of Content Rating 1.3.x+
• Does not yet support XF2.1

• Support for Conversation Essentials for XF2
• Minimum XF2 version is now 2.0.10

• Support Live Content (Thread/Conversations)
• Remove usage deprecated array_column wrapper function
• Update installer

• Fix that content link in summary alerts could not be clicked in alerts pop-up due to CSS styling.