Added Docker file

Dockerfile

@@ -0,0 +1,16 @@
+# Set base image
+FROM node:8
+
+# Set working directory for the app in container
+WORKDIR /app
+
+# Copy package.json to container's /app directory and install dependencies
+COPY package.json /app
+RUN npm install
+COPY . /app
+
+# Launch application
+CMD node index.js
+
+# Expose container's port 8081 to the outside
+EXPOSE 8081