Email notifications for offers received and NFTs sold

Hello.

It would greatly proliferate the offers feature on Gamma if notifications were being sent out when an offer arrives, there's less than X blocks until it expires and when one of your offers is accepted.

Emails for NFTs being sold are also great.

Additionally, I think an in-page dialog should pop-up when you visit Gamma and you have a new offer.
localStorage support for offers that were seen is more than enough.