This adds support for microversion 2.70 which exposes
the 'tag' field in the following APIs:
* GET /servers/{server_id}/os-volume_attachments
* GET /servers/{server_id}/os-volume_attachments/{volume_id}
* POST /servers/{server_id}/os-volume_attachments
* GET /servers/{server_id}/os-interface
* GET /servers/{server_id}/os-interface/{port_id}
* POST /servers/{server_id}/os-interface
Which corresponds to showing the tag in the output of
the following commands:
* nova volume-attachments
* nova volume-attach
* nova interface-list
* nova interface-attach
Depends-On: https://review.openstack.org/631948/
Part of blueprint expose-virtual-device-tags-in-rest-api
Change-Id: I5e9d7e0219605503a56d2cf745b95c6e05d01101
de22cdd3c8