Cleanup cobra integration
Update windows files for cobra and pflags
Cleanup SetupRootcmd, and remove unnecessary SetFlagErrorFunc.
Use cobra command traversal
Signed-off-by: Daniel Nephin <dnephin@docker.com>
Any command that expects extra flags after positional args needs to set flags.SetInterspersed(false).
Signed-off-by: Vincent Demeester <vincent@sbr.pm>