new version for aether-2.0 development

Change-Id: Ibd6979681c8fd8955bed89a2f31090ad5af408d3
diff --git a/VERSION b/VERSION
index dc1e644..fd42787 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.6.0
+2.0.0-dev1