Add CreateAccountViewController and SignInViewController class
Add UI elements in storyboard
Update create account text fields' placeholders
Hook up UI elements to view controllers
Merge branch 'feature/setup_storyboard' into develop
Show coressponding view controllers when create account / login button pressed in signin view controller
Dismiss CreateAccountViewController when create account / cancel button is clicked in CreateAccountViewController
Add USER_NAME and USER_PASSWORD macros
Persist username and password in NSUserDefaults
Check if username/password is not empty and confirm password equals password for create account
Merge branch 'feature/data_persistance' into develop
Check username and password before going to view controller in sign in controller
Show username and password in viewController