Enhance tag mechanism

[OpenStack Infra]

https://review.openstack.org/429621
Dear bug triager. This bug was created since a commit was marked with DOCIMPACT.
Your project "openstack/neutron" is set up so that we directly report the documentation bugs against it. If this needs changing, the docimpact-group option needs to be added for the project. You can ask the OpenStack infra team (#openstack-infra on freenode) for help if you need to.

commit fbf40fe1baac06ce570b660a0a4118e2030c668d
Author: Hirofumi Ichihara <email address hidden>
Date: Thu Jan 19 13:52:39 2017 +0900

    Enhance tag mechanism

    This patch enhances the tag mechanism for subnet, port, subnetpool,
    router resources. The tag-ext as new extension is added so that
    tag supports their resources.

    APIImpact: Adds tag support to subnet, port, subnetpool, router
    DocImpact: allow users to set tags on some resources

    Change-Id: I3ab8c2f47f283bee7219f39f20b07361b8e0c5f1
    Closes-Bug: #1661608
    (cherry picked from commit b56f008f3a01e5dbbf5b0744a9286a8302c3326a)

[Armando Migliaccio (armando-migliaccio)]

We should probably make additions to the base stuff already captured here:

http://docs.openstack.org/mitaka/networking-guide/ops-resource-tags.html

We should review in-tree developer documentation to see whether there's anything missing.

[Hirofumi Ichihara (ichihara-hirofumi)]

Yeah, I'll update devref in Neutron tree.

[Hirofumi Ichihara (ichihara-hirofumi)]

It seems done about OpenStack Manual[1].

[1]: https://review.openstack.org/#/c/430241/

[Alexandra Settle (alexandra-settle)]

Yes, this has been passed and merged.

I'll have to mark this one as a duplicate for manuals: https://bugs.launchpad.net/openstack-manuals/+bug/1662102