--templates option on `overcloud update stack` is unused

[Jiří Stránský]

Passing --templates option into `overcloud update stack` has no effect, it is not referenced in the update code.

If we implement it, we probably need to redo the deployment plan during update init (similarly as if we'd run `overcloud deploy`), and we'd have to implement all the parameters from `overcloud deploy` too. We might want to just remove the --templates option instead, as the current `overcloud update stack` command operates just by slightly altering the existing deployment plan. Further investigation might be in order to tell whether this is sufficient or not.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/539261

[OpenStack Infra (hudson-openstack)]

Change abandoned by Jiri Stransky (<email address hidden>) on branch: master
Review: https://review.openstack.org/539267
Reason: We should do https://review.openstack.org/#/c/540798/

[OpenStack Infra (hudson-openstack)]

Change abandoned by Jiri Stransky (<email address hidden>) on branch: master
Review: https://review.openstack.org/539261
Reason: We should do https://review.openstack.org/#/c/540798/

[Jiří Stránský (jistr)]

We no longer have the `overcloud update stack` command, closing.