VOL-2828 Bump post-2.3 release

Change-Id: Ibedf09550f62982419f26322ace000ad1dce05e8
diff --git a/VERSION b/VERSION
index 276cbf9..eef2640 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.3.0
+2.4.0-dev0