Better docker for the frontend (#240)

* Exclude vscode local settings

* Switch the image to nginx with ENV support

* Add some doc

* Fix travis config

* Ignore coverage data

* Remove version labels

* Fix the Dockerfile according to the recent refactoring

* Cleanup

* Change maintainer

According to @woss request

* Fix travis config

scripts/build-docker-frontend.sh

@@ -0,0 +1,11 @@
+#!/usr/bin/env bash
+
+cd `git rev-parse --show-toplevel`
+
+IMAGE=telemetry-frontend
+DOCKER_USER=${DOCKER_USER:-paritytech} 
+echo "Publishing $IMAGE as $DOCKER_USER"
+
+docker build -t $IMAGE -f packages/frontend/Dockerfile .
+docker tag $IMAGE $DOCKER_USER/$IMAGE
+docker push $DOCKER_USER/$IMAGE