Bug 1074627 - Improve error handling and make more robust

* Improved error handling
* Added cgroups thawing
* Added man page
* Attempt to kill off processes with several methods
Merge pull request #4945 from jwhonce/bug/1074627

Merged by openshift-bot
Merge pull request #4946 from danmcp/master

Merged by openshift-bot
Adding test coverage