Show details of whats changed in puppet summary report

Hi,

Although mco puppet runonce , mco puppet summary is great for telling you there's been a bunch of errors, and a bunch of successes, its just too useful to be able to know what the errors/successes are.

I've added a --detail flag to mco puppet summary which pulls all this info out of the last_run_report yaml file that Puppet generates and displays it in concise a way as possible. 

Now it's extremely quick to do a mass puppet update, and verify that all the changes were expected, and/or drill down if they weren't.

I've tested on puppet2, and assumed puppet3 works in the same way.