bump versions for aether-2.0 development

Change-Id: I4c35b4e6a421d4169ae2a5c7816a70c1d19279ba
diff --git a/VERSION b/VERSION
index dc1e644..fd42787 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.6.0
+2.0.0-dev1