Fix bug 1404: helm2 initialization with new stable repo URL

Change-Id: I30e5a84002c2f5675f0f0403ddaef2383980296f
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>

installers/full_install_osm.sh

@@ -962,7 +962,7 @@ function install_helm() {
         kubectl --namespace kube-system create serviceaccount tiller
         kubectl create clusterrolebinding tiller-cluster-rule --clusterrole=cluster-admin --serviceaccount=kube-system:tiller
         # HELM initialization
-        helm init --service-account tiller
+        helm init --stable-repo-url https://charts.helm.sh/stable --service-account tiller
 
         # Wait for Tiller to be up and running. If timeout expires, continue installing
         tiller_timeout=120;