Specifically add files so they can be cached by Docker.

Dockerfile-webpack

@@ -1,9 +1,9 @@
 FROM node:7.3.0
 RUN mkdir /code
 WORKDIR /code
-ADD ./bikeshop_project /code
+ADD ./bikeshop_project/package.json package.json
 RUN npm install
 RUN npm install -g bower
-COPY ./bower.json .
+ADD ./bikeshop_project/bower.json bower.json
 RUN bower install --allow-root
 EXPOSE 3000:3000