pay 6.x-1.0-alpha2

This release expands the form-handling capabilities of the original pay element, and adds some exciting new functionality:

* A pay_node sub-module, which provides the ability to attach existing payment forms to nodes, or to create a new payment form for each newly-created node. This is useful for pledge drives, contextualized giving forms, purchasing a service, etc.
* Actions and triggers support, which allows you to e.g. send confirmation messages upon payment.
* A pay_progress sub-module, which displays progress towards a particular goal
* Lots of new views handlers and updated views functionality
* Access control on payment forms and payment methods
* Updated and bug-fixed pay_donate module