account verification flows requiring a captcha?

[slingamn]

It's already possible to implement email and captcha verification externally: build a webapp that can dispatch verification emails, display and verify a captcha, then finally SAREGISTER an account with the ircd on success.

But we might want to have better code support for it within Oragono itself. For example, we could let people initiate the registration process in-band, then the external webapp would check the captcha and do a SAVERIFY or something. Or we could serve captchas straight out of Oragono itself.