WIP: Populate league with default teams

@ShaiNirShado 

I'm starting with a spec to fill a new league with 22 teams (20 players, 1 commish, 1 user.). So far, so good, but I'm not sure how to add the 'type'. I may as well also add here that if I were to change Special column to Type or something of the, sort, do I just ned to change the model and then rebuild the database?

Next step after this is to apply similar methods to make 22 default teams in a league. I'm going to assume the league owner will be able to change their names as he sees fit. Do we want to use the default MLB teams here?
Should this be called leagueTest rather than populateTest so there's no confusion that it comes from populate_test.js instead?