IRC command to fave DJs

[Bevinsky]

Some people have requested a command that lets you fave a specific DJ, so that when that DJ starts streaming (as in, calls the .dj command), everyone who have faved that DJ are alerted.

The syntax could be something like
.favedj [dj]

When the command is called, the currenly DJing DJ becomes faved. If the second parameter is specified, that DJ is faved instead. If the DJ is not recognized, nothing is faved and an error message is given.

[Wessie]

Added required models to the project. Will be implemented in a later version.

[ameliaikeda]

Suggestion: remove push notifications from faves and add them to DJ changes.