Addition of CCs/Bank accounts even if form elements not present on page load.

If the form elements for adding bank accounts or credit cards are added to the DOM after initial page load (ie AJAX) the submit button is not present to attach .click() and trigger the calls to balanced.

Fixed by moving each file into their own function, called by a jQuery .on handler on the submit button class which must exist.

Allows the addition of either bank accounts/credit cards even if the form is added after initial page load.
@vadimt ".submit-cc-info" button does not need to exist on page load for this .on event handler to work on it. 

Adding the hooks with the AJAX form partial does not work if they are yielded into the head, as the head is only processed on page load.

It is possible to include the hooks with the AJAX form partial and NOT include them in the head, and the JS will work fine (as you have stated), but this does not fit the README of how to use the gem, thus my commit here.