added factory girl gem to gemfile
Complete test, add user factory & log in helper
Add username to User
Conditionally display sign in/up/out links
fixed user sign-out function
added test to check for unique username during sign up
added uniqueness validation to usernames, corrected migration to add username
correct single quote to double quote per houndci notification
changed log_in_helper quotes to double quotes per houndci notification
Merge pull request #18 from LaunchAcademy/add_factory_girl

RFR - Add factory girl
Resolve merge conflict
Merge branch 'cp_seed_rides' of github.com:LaunchAcademy/ok_bus into cp_seed_rides