add newrelic aws cloudwatch agent

Add the newrelic AWS plugin agent which uses the CloudWatch API to gather statistics and send to newrelic.

Only question I have is if the bundle install is necessary within the upstart script. In RVM, I had trouble getting the bundled gems properly setup during bootstrap, so I also bundle installed during upstart. It seems to work now with ruby-build, but the bundle install doesnt hurt anything.  

Feel free to add your thoughts.