Updated VERSION file to 2.2.0-dev

Change-Id: I45ff53e4325f3bbaaa5c7894e936580d1cbf0fbc
diff --git a/VERSION b/VERSION
index 7ec1d6d..97ade15 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.1.0
+2.2.0-dev