Since DCOM is not supported in corefx there was a great deal of dead code in the computer cmdlets.
This PR removes all vestiges of DCOM support from:
- Rename-Computer
- Restart-Computer
- Stop-Computer
removing about 4500 lines of dead code. Also, tests are updated to provide more complete coverage.
I also removed test-connection completely to make way for @iSazonov upcoming PR to improve coverage in tests, I created some test hook code which will test the cmdlet code without actually calling the WMI method to restart/rename/stop the system