VOL-2030 Return to -dev version

Change-Id: Ica48ca921cf9c787ff477a61f7eab0c703107873
diff --git a/VERSION b/VERSION
index ccbccc3..84e6d84 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-2.2.0
+2.2.1-dev