Docs: Correct i18n information
Docs: Correct i18n information

The internationalization devref information was out of date from our current
practices. Updated to show the correct translation markers to use and fix
example showing bad practice of mismatches marker and pre-formatting of
message string.

Change-Id: I16c34704c338979bafc7f04474d6f3d427276bed

phenoxim/cinder,Datera/cinder,phenoxim/cinder,openstack/cinder,j-griffith/cinder,eharney/cinder,Nexenta/cinder,Nexenta/cinder,Hybrid-Cloud/cinder,mahak/cinder,mahak/cinder,NetApp/cinder,j-griffith/cinder,cloudbase/cinder,ge0rgi/cinder,cloudbase/cinder,openstack/cinder,Datera/cinder,eharney/cinder,NetApp/cinder,Hybrid-Cloud/cinder