Shift to Stat dashboard panel
This release includes an upgrade to the wa_status dashboard, which now uses the Stat panel (as the SingleStat panel previously used is now depreciated).
It also includes the reporting of the daily change of records in our Solr trackdb service, and removes the alert of another Solr server warning that it is very low on diskspace (which in reality is okay as the amount used is high but constant, not increasing). A new alert now exists for this server just in case its diskspace reaches < 5%.