Updating documentation with Radisys OLT and released version deployment, using latest openonu-go, moving to 2.9.0 Versions for infra e stack

Change-Id: I7b7836676fa478b8d7d168e91e151aee89c0a2dc
diff --git a/.gitreview b/.gitreview
index 2b11b97..72f9136 100644
--- a/.gitreview
+++ b/.gitreview
@@ -3,3 +3,4 @@
 port=29418
 project=voltha-helm-charts.git
 defaultremote=origin
+defaultbranch=voltha-2.8