Fix hooks for prepareheading and preparerow
Add filters and rows for sent and recipient for regcode_mailer

Fixes http://drupal.org/node/617164, which occurs when no modules implement that hook, resulting in an empty edit array.
Fixes http://drupal.org/node/662932, which is fixed as a result of the 617164 fix

Add pager information

Fix bug where rules module is called with invalid regcode
Polish off submodules roles and mailer

Finish refactor and commit working implementations of the regcode module, and two working plugins for mailing and automated group assignment

- Adds support for trigger module
- Provides a modular hook system for plugins
- List page needs huge refactor (half way there) to allow plugin actions and filters

- Rule creation interface
- Rule management and listing
- Rule application during registration

- Adds send regcode via email support

- Patch provided by JacobSingh