Update singleusergroup plugin
Update singleusergroup plugin

* Use account index to suggest user groups

Change-Id: I48fa6358708b14bed97ca54a5aefcb4c407c5577
Signed-off-by: Edwin Kempin <d43fb6c98c97e553b671ed9a9318100f1de386e7@google.com>

gerrit-review/gerrit,GerritCodeReview/gerrit,gerrit-review/gerrit,qtproject/qtqa-gerrit,gerrit-review/gerrit,qtproject/qtqa-gerrit,GerritCodeReview/gerrit,GerritCodeReview/gerrit,WANdisco/gerrit,GerritCodeReview/gerrit,WANdisco/gerrit,GerritCodeReview/gerrit,qtproject/qtqa-gerrit,qtproject/qtqa-gerrit,GerritCodeReview/gerrit,gerrit-review/gerrit,qtproject/qtqa-gerrit,WANdisco/gerrit,qtproject/qtqa-gerrit,WANdisco/gerrit,qtproject/qtqa-gerrit,WANdisco/gerrit,gerrit-review/gerrit,WANdisco/gerrit,GerritCodeReview/gerrit,gerrit-review/gerrit,gerrit-review/gerrit,GerritCodeReview/gerrit,WANdisco/gerrit