Bumping minor versions after VOLTHA-2.7 release

Change-Id: I9acfc611280826f13ec4845f3f2932e1d42571f4
diff --git a/voltha-stack/Chart.yaml b/voltha-stack/Chart.yaml
index 74398ba..6d0f1fe 100644
--- a/voltha-stack/Chart.yaml
+++ b/voltha-stack/Chart.yaml
@@ -27,8 +27,8 @@
     url: "https://www.opennetworking.org"
 name: voltha-stack
 
-appVersion: "1.0"
-version: 0.1.17
+appVersion: "2.8-dev"
+version: 0.2.0-dev
 
 dependencies:
   - name: voltha