Relay improvements, spam control

[franzaps]

• Gossip/outbox models when users are logged in
  • https://mikedilger.com/gossip-model/
  • NIP-05, nprofile fallbacks
  • see NDK
• Right now you can pass your own relays to the widget. These are used for both reads and writes. Perhaps I could make that attribute only apply to read-relays, and use the gossip/outbox model for writing to each users' relays
• remote signing NIP-46?

[Giszmo]

I think the plugin user should be able to add relays for writing but the plugin should also write to the respective user's relays.