bumping to version 2.0

Change-Id: Ifff5119d89784fab785fce66d8289c134588e95f
diff --git a/.gitreview b/.gitreview
index 328aec6..c6cb2df 100644
--- a/.gitreview
+++ b/.gitreview
@@ -3,4 +3,4 @@
 port=29418
 project=onos.git
 defaultremote=origin
-defaultbranch=master
+defaultbranch=onos-2.0