Removing code which disables a Pay Form when the related Pay enabled node is deleted. Pay forms can have their own callback or be used in multiple places.

Removing pass by reference for $form as this was causing issues with saving forms in Drupal 7 on PHP 5.3. Also removed the destination argument and form code as this was rendered in operable. This code was originally added for Donate to direct users back to the donate form listing after adding or editing a donation form. This is now being handled in the submit method for Donate.

Add a form handler selection for views.  This provides a user-selectable list of pay_form handlers during views configuration.

When querying for a list of payment forms filtered by handler, ensure that the subclasses of that handler are also included.  This allows you to be extend a pay_form handler without having its entries omitted from the list.

Update handling of currency-setting.  Allow users to update global currency _only_ if there are no existing transactions that use the currency.  This means you can futz with currencies all you like, until you've started creating transactions.

Add a set_currency() function to pay_transaction.  Defaults to $pay_form's currency (which in turn probably defaults to the globally-selected currency).

Add a currency_list() method for payment forms.  By default, this will only return the globally-available currency.  If an as-yet-unwritten module variable_sets pay_currency, it will also return a list of currencies supported by its payment methods.

Rewrite pay_currency_list() so that it's not using a hard-coded list of USD & EUR (how presumptuous!)

Instead, create a superset of all currencies supported by all payment method handlers installed on the site.

Add an available_currencies() method to pay_method.  The expectation is that all payment methods implement this to identify the currencies that they support.

- Always save transactions when an activity fires

As it turns out, we do use the 'authorize' action for more than just pay_method_gateway.  Re-add it to pay_method, and re-remove it from pay_method_custom.

Move some functions around for cleanliness.  Make sure that payment method values get sent to the gateway provider correctly.

Refactor the form_submit function for direct payments: Do not assume that all submissions will use this payment activity, and do not rely on form submissions to collect and store values.

Add set_direct_pending(), which will do most of what a gateway needs it to do - which is save its submitted data and set the current activity to 'pending'.  

The expectation is that the 'response' will create a second activity after the customer has completed payment on the gateway site.

Optionally pass in an array of values to payment actions.  On pay_form submissions, populate this with the values submitted for a particular payment method.

Implement views handling for payment transaction states, which allows filtering/sorting/aurgumenting/fielding of said states.

Add some helper functions to pay.module to help facilitate this.