Notify all players (signups + waitlisted) when an event is dropped

[dkapell]

Ace Tayloe says: Feature request (possibly a feature modification request): If a game gets canceled, send out an automatic email informing all players and waitlisters of the cancelation. (Source: A friend was waitlisted for High Tea, which got canceled; they didn't get a notification about the cancelation, and only found out today when they checked the site.)

[dkapell]

Dave says: There may be times when Con staff wishes to remove an event without notification, but maybe that should be an option on the drop event confirmation dialog.

[marleighnorton]

Yes, notifications make sense. We should do that. Usual rules (e-mail always, also text if enabled)