add devise, generate user model
bootstrap 3 + some layout html
override devise user sessions
create player, coach and parent models. write tests
add flash messages styling
create registration page, add datepicker functionality
add gender virtual attribute, write specs
write specs for session controller
add inverse_of to models
Add Database cleaner gem
implement registration
Merge pull request #2 from Minisai/R-5_impelementing_authorization_for_each_kind_of_users

R-5: Impelementing authorization for each kind of users