Machine Specifications added to SpecWatchr

Added Machine.Specifications as an additional test_runner in dotnet.watchr.rb.
Implemented the new MSPECTestRunner inside of watcher_dot_net.rb

![image](https://f.cloud.github.com/assets/1062417/378186/89990734-a522-11e2-94db-783e0fdd875b.png)

I hope this helps some folks that want to use Machine.Specifications with SpecWatchr.

I would love some feedback with how I implemented the runner as i'm quite new to ruby.