Fix "glance add" parsing of "copy_from" option.
Fix "glance add" parsing of "copy_from" option.

copy_from was ignored which resulted in "glance add" attempting to read from
stdout.

Fixes bug 1167899

Change-Id: I57fd85f7bb655bef69222d4fdf6b8274088ca827

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