* Check if the MediaDevices API is not suported and fall back to file
  upload.
* Expire old images after some reasonable amount of time. This can be done
  with just a find command.
* Add systemd service file and Makefile to install it better.
* Improve CSS. (Patches welcome on this one.)
* The javascript could let things be added in offline mode, and sync up
  with the server next time it comes online. (Patches welcome on this one.)