readme, docker update

Dockerfile

@@ -18,10 +18,15 @@ USER badgedex
 COPY --chown=badgedex:badgedex . .
 
 #Install dependencies
-RUN npm ci --only=production
+RUN npm ci --omit=dev
 
 # Expose API port
 EXPOSE 3000
+
+# Health check
+HEALTHCHECK --interval=30s --timeout=5s --start-period=5s --retries=3 \
+  CMD wget -qO- http://localhost:3000/version || exit 1
+
 #Start node application
 ENTRYPOINT ["npm"]