Ability to use plugins without compiling them into root CLI

[ankithans]

The ability to run the CLI plugin with the binary, can be done by keeping the registry for supported plugins
#37 provides somewhat fair example to this

[wtrocki]

Note that this is not full blown registry - just code to call binary that is either:

• installed in the system
• documented to be installed and failover if not
• There is no need to have list/install commands etc.

Copying exact comment as link brings us to the entire PR:

Calling external CLI is a very cool although a commonly resolved problem in the golang ecosystem.
I do not want to steal cool feature from you and we can keep this as capability, but I did not think that people will use charmil for that where you can have this:

https://github.com/kubernetes/kubectl/blob/master/pkg/cmd/plugin/plugin.go

https://github.com/openshift-online/ocm-cli/blob/master/pkg/plugin/plugin.go

https://github.com/openshift/odo/blob/main/pkg/odo/cli/plugins/plugin_handler.go

[wtrocki]

This is epic that is outside the scope of the GSOC for now