add credit card model
add credit card
update readme
move payments from BankAccount to User
check if user has a valid payment method
make payments with user's payment method
prompt user to choose payment method
show correct payment links based on user state
redirect to payments path after adding payment method
add message about 2.9% fee
add errors to new credit card and bank account forms
add polymorphic associations for payments
change primary_payment_method to return a BankAccount or CreditCard
seperate concern of fetching balanced account object
charge user processing fee when they pay with credit card
add backwards-compatible migration for polymorphic associations
move start payment buttons to payments#index
improve readability
remove 'method' column from payments

exit
dd
delete old cassettes from spec folder