Ignore all the build directories in Docker

This allows for reproducible builds.
Also, fix Dockerfile to first build and then run tests and a typo in the entrypoint.

Thanks @BenHall for reporting the issue with the Docker build!

.dockerignore

@@ -1,2 +1,16 @@
-node_modules
-.git
+node_modules/
+*.swp
+.lock-wscript
+lib/
+Makefile.gyp
+*.Makefile
+*.target.gyp.mk
+*.node
+example/*.log
+docs/
+npm-debug.log
+/.idea/
+.env
+build/
+.vscode/
+.git/

Dockerfile

@@ -10,7 +10,7 @@ RUN apt-get update \
 WORKDIR /usr/src/app
 
 # Set an entrypoint, to automatically install node modules
-ENTRYPOINT ["/bin/bash", "-c", "if [[ ! -d node_modules ]]; then npm install; fi; exec \"$@\";"]
+ENTRYPOINT ["/bin/bash", "-c", "if [[ ! -d node_modules ]]; then npm install; fi; exec \"${@:0}\";"]
 CMD ["npm", "run", "dev"]
 
 # First, install dependencies to improve layer caching
@@ -21,4 +21,4 @@ RUN npm install
 COPY . /usr/src/app
 
 # Run the tests and build, to make sure everything is working nicely
-RUN npm run test && npm run build
+RUN npm run build && npm run test