add devise gem
configure action_mailer host
install devise
add navbar
remove unneeded elements from navbar
add custom registration routes
remove homepage link
write validation test for username on user model
add username to user model
add devise configurations for username
generate devise views
refactor devise routes
remove unneeded links
create configure_permitted_parameters method
refactor edit_profile page
add line breaks
add line breaks
add line breaks
refactor text in navbar
rename and refactor flash messages partial