Added debug script to easily test changes and to have a sample of a debug run ready.
IntelliJ Project update
Reduced mail size to 10MB (plain-text)/5MB (HTML) to avoid getting filtered out by sourceforge's mailer daemon.

 Added a debug-flag that prints commit messages to Sdt-out instead of sending it via SMTP.

  Filtered out bogus "Unexpected:" mails when a ref was updated.
  GitHub does not allow us to run the script on their servers, so we have to
  mirror their repository. That pulls in remote tracking refs as well, and we
  don't want update notifications on them.

  Added specific message-handlers for pull requests to track their creation and
  their merge time.
Fix RegExp for pull requests