Add gitpod config (#1786)

this commit adds support for Gitpod.io, a free automated
dev environment that makes contributing and generally working on GitHub
projects much easier. It allows anyone to start a ready-to-code dev
environment for any branch, issue and pull request with a single click.

Co-authored-by: Steven Ickman <stevenic@microsoft.com>

Author: diogocbarros

.gitpod.Dockerfile

@@ -0,0 +1,10 @@
+FROM gitpod/workspace-full
+                    
+USER gitpod
+
+# Install custom tools, runtime, etc. using apt-get
+# For example, the command below would install "bastet" - a command line tetris clone:
+#
+# RUN sudo apt-get -q update && #     sudo apt-get install -yq bastet && #     sudo rm -rf /var/lib/apt/lists/*
+#
+# More information: https://www.gitpod.io/docs/config-docker/

.gitpod.yml

@@ -0,0 +1,4 @@
+tasks:
+  - init: npm install && npm run build
+image:
+  file: .gitpod.Dockerfile