Add remaining image API ref
Add remaining image API ref

This commit adds remaining image and metadata API ref
and also correct the existing one with status code and
sample file name.

Part of bp:api-ref-in-rst

Change-Id: I9db88b0ad042501406d512e417440a1146027326

mahak/nova,mahak/nova,openstack/nova,rahulunair/nova,vmturbo/nova,Juniper/nova,sebrandon1/nova,jianghuaw/nova,bigswitch/nova,gooddata/openstack-nova,gooddata/openstack-nova,openstack/nova,klmitch/nova,sebrandon1/nova,mikalstill/nova,vmturbo/nova,Juniper/nova,hanlind/nova,vmturbo/nova,mahak/nova,rajalokan/nova,rahulunair/nova,mikalstill/nova,gooddata/openstack-nova,rahulunair/nova,jianghuaw/nova,jianghuaw/nova,mikalstill/nova,gooddata/openstack-nova,cloudbase/nova,vmturbo/nova,klmitch/nova,klmitch/nova,klmitch/nova,phenoxim/nova,sebrandon1/nova,rajalokan/nova,phenoxim/nova,hanlind/nova,bigswitch/nova,Juniper/nova,rajalokan/nova,Juniper/nova,cloudbase/nova,openstack/nova,jianghuaw/nova,alaski/nova,cloudbase/nova,hanlind/nova,alaski/nova,rajalokan/nova