Code clean-up

I've gone through the module code by hand and using coder.module and fixed some code style issues:

* Fixed issues reported by coder.module
* Fixed grammatical errors
* Removed commented-out code
* Fixed PHP errors
* Removed irrelevant comments
* Removed sponsorship texts

I know the last one may not be desirable for the module maintainer. I believe sponsorship information should go into a README.txt file and/or on the module page at Drupal.org, but not in the module itself. The same with the comments at the top of comment_notify.module with wishlists and whatnot. That's not where most people will look for that information.

There should be no functional changes from this patch other than a PHP error fix (see http://drupal.org/node/191313).