Change all example urls in doc/source to
http://glance.openstack.example.org
Change-Id: If7a5ccd31f6892de441d2acb6213bf15d1be3e64
Closes-Bug: #1611489
Co-Authored-By: Jin Li <jl7351@att.com>
Co-Authored-By: Hemanth Makkapati <hemanth.makkapati@rackspace.com>