Disable cert verification for client certs? about rustls

[ctz]

I think I'm kind of softening on this as time goes on. But stuff like this is still going to always be behind a scarily-named feature, and probably exposed in a deliberately obtuse place in the API. I guess this is similar to PR #64

[alex]

I am ok with that; I solemnly swear that I'll never use the scarily named option without a long comment explaining why in this very narrow context it's ok.

If you can suggest where in the API you'd like it, I'm happy to send a PR.

[alex]

Here's a proposal:

• New feature dangerous_configuration, which you have to enable in order to be able to use this stuff
• On rustls::ServerConfig add a dangerous_configuration field, which is an instance of Option<rustls::DangerousServerConfig>
• rustls::DangerousServerConfig has a disable_certificate_verification bool field
• None of these fields exist unless the dangerous_configuration feature is enabled.

I think this makes things relatively inaccessible -- it also means that if a library wants to use all this, it's clearly propagated in a way that consumers can see it.