Rancher: [cli] Add/change host label

[Kamaradeivanov]

According to the forum ticket (https://forums.rancher.com/t/add-change-host-label-via-rancher-cli/4256), I create an issue for the following feature.

I would like to add or update a label on a existing host. Actually I can only add labels during the host creation.

[Gmentsik]

Any update on this? This would be really usefull....

[anjia0532]

This is really really really usefull.

[deniseschannon]

With the release of Rancher 2.0, development on v1.6 is only limited to critical bug fixes and security patches.