Kfsio lib: add cert depth parameter to peer name verify method. Only compare names at the 0 depth in SslFilterPeerVerify::Verify().
Meta server: change client state machine and chunk server state machine to verify / use the name of the top level (zero depth) certs.
Kfsio lib: set authenticated name to the common name of the top level X509 cert, in the case if no verification object set.