Create the Team model: a object for holding Team information.
All current and former Teams are automatically instantiated in the pyAFL.teams module. Team objects can be imported by their team abbreviation. For example: from pyAFL.teams import ADE, SYD, RIC
The API allows querying historical team players (e.g. ADE.players)
The API allows querying historical game results (e.g. ADE.games)
Addresses Issue #3