Cherry-pick graceful LB changes#2157

Merged

fcrisciani merged 2 commits intomoby:bump_17.06from

ctelfer:bump_17.06

May 23, 2018

Commits on May 22, 2018

Delete service info from cluster when service is disabled

abhi
authored and
ctelfer
committed
Gracefully remove LB endpoints from services

ctelfer
authored and
Flavio Crisciani
committed