helm install - write output to file (#1412)
helm install - write output to file (#1412)

updated the helm install command to write output to istio.yaml, see
https://github.com/istio/istio.github.io/issues/1409

(cherry picked from commit 773899b)

geeknoid/istio.github.io,geeknoid/istio.github.io,linsun/istio.github.io,istio/istio.io,istio/istio.io,istio/istio.io,geeknoid/istio.github.io,geeknoid/istio.github.io,ZackButcher/istio.github.io,istio/istio.io,linsun/istio.github.io,linsun/istio.github.io,istio/istio.io,istio/istio.io,linsun/istio.github.io,geeknoid/istio.github.io,istio/istio.io,ZackButcher/istio.github.io,ZackButcher/istio.github.io,ZackButcher/istio.github.io,linsun/istio.github.io