Update 0.6.0: Docker support

Dockerfile

@@ -0,0 +1,18 @@
+FROM keymetrics/pm2:latest-stretch
+# Create app directory
+WORKDIR /usr/src/markbot
+
+# Install app dependencies
+COPY package*.json ./
+
+# If you are building your code for production
+ENV NPM_CONFIG_LOGLEVEL warn
+RUN npm ci --only=production
+
+# Bundle app source
+COPY . .
+RUN mkdir config
+
+RUN ls -al
+
+CMD [ "pm2-runtime", "start", "ecosystem.config.js" ]