As a member, when I request a seed trade from another member, currently all that happens is they get a PM from me, and we then sort things out between ourselves.

It would be good to actually track seed trades in the database.

A seed trade would have:

• seed_id -- the seeds being requested
• requester_id -- the member requesting it
• message -- text message from one person to another
• address -- postal address to send to (NOTE security issues! might want to have SSL before we do this; also make sure not to expose it via API etc)
• requested_date
• accepted_date
• declined_date
• sent_date
• received_date

The process would be:

• A requests seeds from B
• B is notified of request
• seed trade shows up in lists visible to both A and B (eg. "my seed trades")
• B accepts request; accepted_date is set
• OR B declines request; declined_date is set
• B can then mark as sent when they've been sent; sent_date is set
• A marks it as received when it has been; received_date is set