* Pin spf13/cobra dep at b95db644ed1c0e183a90d8509ef2f9a5d51cc29b
which includes the zsh completion fix for https://github.com/spf13/cobra/pull/899
and remove the fork of cobra with fix in `replace` section of go.mod
* Parse args without invoking a separate command
Do not define and execute extractCommand before running actual root
command to parse all the args without flags. This was creating issues
with completion utils to generate additional shell completion directive.
Now uses cobra's inbuilt utilities to parse the command args without flags.
* Return error from stripFlags if any
* Update unit tests
David Simansky