Docker-Compose Single-Run

Add firstrun checks

Avoids running commands on firstrun
Add Docker-compose file

allows setup in a single docker-compose up command
Updated Readme re: docker-compose

Added stub detailing how to use the compose file.
Update README.md
Changed Entrypoint

Moved sanity checks to their own script, changed entrypoint logic
updated entrypoint

Dockerfile

@@ -30,4 +30,4 @@ USER appuser
 
 EXPOSE 8080
 
-CMD [ "./webserver.sh" ]
+ENTRYPOINT [ "./entrypoint.sh" ]