Bump minor version post VOLTHA2.4 branch out

Change-Id: Id4cd2d37a9375ecdfbc18f39155e1b71b4c45656
diff --git a/VERSION b/VERSION
index 53a75d6..d510910 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.2.6
+0.3.0-dev