Initial Sinatra skeleton

-Includes BCrypt gem, includes module and user authentication methods in User model, password_hash field in :users migrations table
-Includes RESTful routes for user creation, login, and profile
-Includes Post/Redirect/Get route design pattern
-Includes Quickstart and Troubleshooting guide in README
-Includes views for user creation, login, and profiles
-Includes configuration notes explaining how and where ActiveRecord looks for files