For clarity, on `docker context use` or `docker context ls`, this adds a
warning if the DOCKER_HOST variable is set because it overrides the
active context.
Signed-off-by: Simon Ferquel <simon.ferquel@docker.com>
This will allow plugins to have custom typed endpoints, as well as
create/remove/update contexts with the exact same results as the main
CLI (thinking of things like `docker ee login https://my-ucp-server
--context ucp-prod)`
Signed-off-by: Simon Ferquel <simon.ferquel@docker.com>