Implement post-undeploy cleanup for KVM (TUI-108)

Cleanup everything on undeploy

Minor refactoring + fixes
Destroy on undeploy only if VM was running (TUI-108)
Compile cleanup list before the domain is actually undefined (TUI-108)
utils is under actions (TUI-108)
Fix XPath syntax in compile_cleanup (TUI-108)
Python 2.6 ElementTree does not support much of XPath, reimplement with plain code manipulation (TUI-108)
Remove superfluous comment (TUI-108)
Fix typost (TUI-108)
Merge pull request #146 from opennode/tui-108

Implement post-undeploy cleanup for KVM