This runtime should not include a copy of the nodejs proxy server

[csantanapr]

This runtime should not have a copy of the OpenWhisk proxy server.

Options:

1. We could extend the image from OpenWhisk nodejs 8 in the Dockerfile

FROM openwhisk/action-nodejs-v8:1.5.0
....

2. Fetch in the Dockerfile the app.js, runner.js and src/service.js from https://github.com/apache/incubator-openwhisk-runtime-nodejs/tree/master/core/nodejsActionBase
   like the OpenWhisk python runtime does for the proxy https://github.com/apache/incubator-openwhisk-runtime-python/blob/master/core/python2Action/Dockerfile#L53

I think I preferred option 1.

cc @eweiter

[csantanapr]

This is already done