Corrects JOIN logging, which didn't check whether the message was for us

Corrects JOIN logging, which didn't check whether the message was for us or another user. Fixes that `saveBackup` was was run more frequently for each time a user entered the room, or we reconnected.

Adds logging for our IRC kicks and connections, so we'll know if it's had any trouble. (Unfortunately this IRC library doesn't seem to have any explicit `disconnect` events, so we can't collect data on that beyond knowing when it reconnects.)