File upload quota

To prevent abuse of the service I'd recommend setting a file upload quota.

First a quota by time:

mod_http_upload_quota:
    max_days: 14

And a quota by disk space:

shaper_rules:
  ...
  soft_upload_quota:
    - 1000: all # MiB
  hard_upload_quota:
    - 1100: all # MiB
  ...