Add roles and membership types

When talking to Robert, it became apparent that Hive Chicago will need some notion of "organization type" to use the directory effectively. In Hive Chicago, organization types include e.g. "partner" and "affiliate".

There is actually a notion of memberhsip types in Hive NYC, too, we just don't surface it yet--there are "full" member orgs who can apply for grants, and "community" members who can't.

Hive Chicago also needs to be able to have admins assign roles to individuals, such as "funding liason" and "activity representative". In some sense these are just like administratively-assigned tags for users, and they're currently displayed as such on user profile pages using [Bootstrap labels](http://getbootstrap.com/components/#labels).