WIP: Client verification

[kleskjr]

verifing clients's public certificate and public key before establishing a secure connection

[oroulet]

I have no idea if check is correct but it looks simple and valid. For storing certificate I propose that you make a new class called CertificateStoreInMemory or similar with a few methods like add_certicate an check_certificate (cert) and set_checker. Then add a method to InternalServer called set_certicate_store.Thus people can make their own implementation later. The certificate validation itself should be done in InternalServer or wherever you think is best

[oroulet]

Maybe make a CertificateStoreInterface too with all methods raising NotImplemented