VOL-2828 Bump post-2.3 release

Change-Id: I63a5bdff2abca5d28f394dd62d26477c92ec392e
diff --git a/VERSION b/VERSION
index 237bbfe..c220681 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.1.7-dev
+1.2.0-dev0