TODO for first release

[mikedilger]

• [x] remove debugging from nostr.rs
• [x] nostr.rs - make sure early errors reply to the caller with something, and improve that something as soon as we can
• [x] on nostr.rs::event(), scan subscriptions and send if filters match
• [x] nostr.rs::validate_event() should check signature (put option in config file)
• [x] output buffer length checking needs work
• [x] When fetching replaceable events, return only the latest.
• [x] finish testing in event_store.rs
• [x] event_store.rs should not just presume Out of Space, check better
• [x] verify all be and ne are correct. Fix json_event test FIXME about big-endian machines
• [x] AUTH
• [x] Restrict some REQs to require AUTH; Make sure I'm doing CLOSED with auth-required prefix on REQs that need auth (this turned out to not be necessary, we just don't supply such events)
• [x] Filter events loaded by REQ to unapproved users - only events authored by approved users, or a few other kinds.
• [x] Allow ephemeral events from everybody?
• [x] NIP-04 compliance (DM)
• [x] NIP-09 compliance (delete)
• [x] NIP-59 compliance (GiftWrap)
• [x] Banning at IP level
• [x] a natural ban of 4 seconds after any close.
• [x] Max subscriptions in config, 32 by default
• [x] User documentation describing configuration settings and relay behavior