Create the confirmation of bank account verifications

It also create new Bank Account verification after 3 failed attempts (close #19)
Require user to be logged in on confirmations#create #29
Improve language on remaining attempts
Add missing user class in dummy app
Fix typos and improve specs messages
Improve readability of a method in confirmations controller
Get last bank_account
Merge pull request #28 from neighborly/jl-confirm-verification

Create the confirmation of bank account verifications