Edit build_sphinx options.
Edit build_sphinx options.

To better facilitate the building and publishing of sphinx
documentation by Jenkins we are moving all openstack projects with
sphinx documentation to a common doc tree structure. Documentation
goes in project/doc/source and build results go in project/doc/build.

Change-Id: Idf3e4472f91a1f5ae36e64b339bef99d4d960b88

varunarya10/python-glanceclient,ntt-sic/python-glanceclient,citrix-openstack-build/python-glanceclient,alexpilotti/python-glanceclient,metacloud/python-glanceclient,ntt-sic/python-glanceclient,openstack/python-glanceclient,JioCloud/python-glanceclient,openstack/python-glanceclient,citrix-openstack-build/python-glanceclient,mmasaki/python-glanceclient,metacloud/python-glanceclient,mmasaki/python-glanceclient,JioCloud/python-glanceclient,klmitch/python-glanceclient,alexpilotti/python-glanceclient,klmitch/python-glanceclient,varunarya10/python-glanceclient