Dockerizing Parse Server (#3005)

* Add Dockerfile

* Add Docker image docs

* Remove default PARSE_SERVER_CLOUD_CODE_MAIN setting + update docs

* Update docs

* Update documentation

Dockerfile

@@ -0,0 +1,21 @@
+FROM node:boron
+
+RUN mkdir -p /parse-server
+COPY ./ /parse-server/
+
+RUN mkdir -p /parse-server/config
+VOLUME /parse-server/config
+
+RUN mkdir -p /parse-server/cloud
+VOLUME /parse-server/cloud
+
+WORKDIR /parse-server
+
+RUN npm install && \
+    npm run build
+
+ENV PORT=1337
+
+EXPOSE $PORT
+
+ENTRYPOINT ["npm", "start", "--"]