Read glance protocol, port for glance_api_servers

Currently glance_api_servers is being in nova.conf set as
    glance_host:9292
It should be:
    glance_protocol://glance_host:glance_port
to allow inclusion of SSL setting (of https) for protocol

Currently glance_port is hardcoded and protocol is assumed,
this change reads the value set in the yaml configuration file.

Change to the yaml file to put the value in as configurable is:
    I3c7218292797c62c36e2aaab4f325bf053ef140b

Depends on: I5fe952f850339465de128e56e45c9bbda011ce7f
Change-Id: Idccc0d60c9f6b17a853c6de1bbea64bfc7e028b2
Merge "Read glance protocol, port for glance_api_servers"