This patch fixes the issue of unauthenticated users, being able to
upload files, even when anonymous edits are disabled.
It's implemented by blocking uploads when either `allowAnonymous` is set
to `false` for all unauthenticated users, unless `allowAnonymousEdits`
is set to true, to make sure anonymous editors still experience the full
feature set.
Signed-off-by: Christoph Kern <sheogorath@shivering-isles.com>