User team assignment

[Ianphorsman]

Implement teams.

Create json file storing teams that can be read and written to by players of that team.

Give users a team attribute so that the user can be associated with the correct team file.

[basicxman]

• Multiple teams
• User is assigned to a single team
• Half-op privileges required to assign a user to a team
• Users can be assigned to a random team
• Op privileges required to create a team

!team mike_n_7 red # Assign mike_n_7 to team red
!team mike_n_7 random # Assign mike_n_7 to a random team
!team red # Create the red team
!team mike_n_7 # Print the team mike_n_7 is on
!team # Print available teams