Simplify docker configs

Dockerfile

@@ -1,17 +1,9 @@
-FROM node:7
-ENV IS_DOCKER 1
-RUN env
+FROM node
 
+WORKDIR /app
+ADD . /app/
 RUN apt-get update
 RUN apt-get install nasm
-RUN npm install webpack -g
-WORKDIR /tmp
-COPY package.json /tmp/
-RUN npm config set registry http://registry.npmjs.org/ && npm install
-
-WORKDIR /code
-COPY . /code/
-RUN cp -a /tmp/node_modules /code/
-RUN webpack
-
-EXPOSE 3000
+RUN npm ci
+CMD ["npm", "start"]
+EXPOSE 8080