UC-1316: Change in IM-display name does not get reflected in Unite

-found issue imDisplayName not replicated in vcard when user is created
it gets replicated only when you manually update it later on - fixed
-unite uses first name and last name info from vcard and not <FN> tag value
and this is why does not get updated - this can be changed in unite to use <FN> value instead
from openuc point of view everything else is good
Merge branch 'UC-1316' into release-4.6