Adding the capability to configure settings for http_proxy https_proxy
and no_proxy inside glance_api container. This is required when import
images from external http resources behind a proxy.
Co-Authored-By: Paul Bourke <paul.bourke@oracle.com>
Closes-bug: #1775815
Change-Id: I85661f04311d5671adecc84c470f2e4db07cfe1d