`First` pass at initial models

# Dependency Changes
* Added south dependency and generated initial migrations
* implicit postgres dependency? with south migrations

# Stability
* Models are all relating properly and auto-registered with admin
* no initial data yet [look at https://github.com/joke2k/faker maybe]
* front end isn't touched

# Applications
## Curling
* deals with the running of the leagues down to throwing of rocks (probably too fine grained for Ottawa Granite purposes; was thinking of a 'managing a bonspiel' level of info initially)
* each league every year is new league, each team new team; likely needs to add `League` and `LeagueInstance` models tying into `membership.season`

## Finance
* VERY quick start at fee generated and payment accepted

## Membership
* Deals with members and associated info
* First pass at Season/Recurring relationship

## OttawaGranite
* models is abstracting a bit from `membership` with additional info most/many clubs wouldn't track; maybe shouldn't be at this point. I was trying to keep it generic enough for lots of applications in `membership` to be used in a more general project for other curling rinks, but it might be easier to pull it out later.