Including igmpproxy change and olt documentation

Change-Id: If949bd615a0a5b2fd43a9db7f4c28dfcff14415c
diff --git a/VERSION b/VERSION
index eb623ad..ca5f454 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.3.1-dev
+4.3.1-dev1