Use CERN username instead of user.<vomsid> for setting IAM account username for LHC VOs

[andreaceccanti]

voms-importer/vomsimporter.py

Lines 289 to 301 in 0a55ce2

	def build_username(self, voms_user):
	user_id = "user.%d" % voms_user['id']
	if self._username_attr is not None:
	for attr in voms_user['attributes']:
	if attr['name'] == self._username_attr:
	return attr['value']
	logging.error("Attribute %s not found for user %s. Will fall back to default username %s",
	self._username_attr, voms_user['id'], user_id)
	return user_id
	else:
	return user_id

[vokac]

It seems to me that just running sync script with --username-attr=nickname should work at least for ATLAS.