add possibility of using public_urls for benchmarking

Add 'use_public_urls' option to the deployment config
This option will be used later for switching access method to the cloud.
Because in some use-cases cloud may be accessible only by public endpoints.

Add 'admin_port' option to the deployment config
This option defines administrative keystone port on the public network.

Closes-Bug: #1306448

Change-Id: Ifb838c5fe9eab5e81353d697aa747bd8adf77572
Merge "add possibility of using public_urls for benchmarking"