xF1 Add-on Alert Improvements by Xon 1.5.6

• Tweak wording on Alert Preferences page
• Add phrases for admin changelog

• Respect limit for alert pop-outs

• Simplify SQL that marks alerts as read when viewing content.

• Prevent an SQL error if the user has 65535 alerts and marks another alert as unread.
• When marking alerts as read on a page, do a select first to determine how many alerts are still unread.
  • This is intent to reduce rows locked when doing the UPDATE.
  • If splitting of read/writes is done, this will allow the slave servers to be checked for any outstanding alerts instead of hitting the master.
• Support PREVENT_MARK_READ debug option

• When viewing a user's profile page, mark any relevant alerts from that page as read.
• Add a "mark all as read" link to the alerts page.
• Allow users to not mark-as-read all alerts when viewing account/alerts page, setting is on account/preferences page.
  • Instead of requiring knowledge of the non-documented "skip_mark_read" argument for the same functionality

On viewing a thread sometimes a deadlock occurs when updating the alert total, if so now retry once.

• Ajaxify the "Mark Unread" link

Support marking alerts as read for the following add-ons:

• Post Rating
• Conversation Improvements
• Report Improvements

Improved thread handling, so when new posts are viewed on replying to clicking the 'show more posts' link, and relevant alerts are marked as read.

Minor tweaks to reduce the risk of deadlocks when marking alerts as read.