Merge pull request #65 from Dykam/master

Allow commands to be executed on alert
Fix #851

Fix for https://snowy-evening.com/issues/details/479/851/
Need to join while delete :)
Only need left join
Merge pull request #66 from Xephi/master

Adding prism_data_extra join for purges, bug 851:resolved
 Beginning conversion to UUID system being implemented by Mojang. We cache player names and UUIDs to the database, and we'll use those for lookups. Fake players will have a UUID generated for them. The new PlayerIdentification class provides multiple static methods for looking up players based on ID or name. Prism will update the players table with their current username each login. Bug 827
Adding missing player-uuid files