Enables profile creation

Creates polymorphic association between user and profile (either manager or bartender)

* Removes previous structure which was single profile model for both types of users
* Creates new view for manager and bartender profiles with form partials for each
* Creates models and controllers for manager and bartender profiles
No b/c the bartenders are only guest bartenders (i.e., not employees).  A manager could be an employee bartender but not a guest bartender.