VOL-5140 - Create release branch for voltha-openonu-adapter-go

VERSION
-------
  o Bump VERSION file for the next non-release *-dev version.

.gitreview
----------
  o Assign defaultbranch=master to sanity check correct branch/version has been checked out.

Change-Id: I1a9b8dce25e7639c484ac3b4b24b3f658bf08f9d
diff --git a/.gitreview b/.gitreview
index 6e7dab7..797bd40 100644
--- a/.gitreview
+++ b/.gitreview
@@ -3,3 +3,4 @@
 port=29418
 project=voltha-openonu-adapter-go.git
 defaultremote=origin
+defaultbranch=master
\ No newline at end of file