VOL-1598 Update openolt.proto for multicast support

Change-Id: I84a07712070a82a53eba452cb103c32a33b73386
diff --git a/VERSION b/VERSION
index 4a36342..fd2a018 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-3.0.0
+3.1.0