move loading notice on new subscription from to just after the form is submitted
refactor specs for the two-page signup process
refactor tests for 2 page sign-up
route user to verification page if bank account is unverified
route user to show page if bank account is verified, after log-in
confirm a bank verification if correct deposits are entered
not confirm a bank verification if incorrect deposits are entered
set 'verified' to true when a verification has been confirmed