A proposal for a receive-only folder type

[Martchus]

@adi-dev

he can change Receive Only status to something else

@schneemensch

Set your own folder as Sendonly. That way he cannot screw with your data.

@adi-dev

I need to have this folder send/receive with other machines

Reminds me of a previous idea to implement read-only-like behavior: New Folder type: Receive Only - #33 by Martchus