Cruisecontrolrb Cruise Control.rb

The interface of a Net::SMTP has changed in REE 1.8.7 and the CCRb monkey patch no longer applies cleanly (it's calling a private method with the wrong arity).

I've created a problem to fix this issue in a backward-compatible way, such that the monkey patch will call with the expected arity.

In addition I added the ability to configure the subject line for the email notifier, and to only notify on certain events (e.g. notify on build broken but not on build fixed). This allows me to use CCRb not only to run a continuous integration loop, but to monitor for coding standards violations, missing commit comments, and so forth. These two simple features make CCRb a much more versatile tool!

I've added some minimal test coverage for the new features. Kindly consider the patch, attached, which contains a roll-up of all my changes -- I strongly recommend adopting the REE 1.8.7 compatibility stuff even if you vote down the new features.

Thank you for all of your great work,
Tony (still using a fork of CCRb for now...)