This is the one piece of functionality I miss from the openssl tool -
the ability to see some basic information about the server cert.

Sample output:
==========
$ bssl client -connect www.google.com
Connecting to [2607:f8b0:4006:80d::1010]:443
Connected.
  Version: TLSv1.2
  Resumed session: no
  Cipher: ECDHE-RSA-AES128-GCM-SHA256
  ECDHE curve: P-256
  Secure renegotiation: yes
  Next protocol negotiated:
  ALPN protocol:
  Cert subject: /C=US/ST=California/L=Mountain View/O=Google Inc/CN=www.google.com
  Cert issuer: /C=US/O=Google Inc/CN=Google Internet Authority G2
==========

Change-Id: I758682784752a616628138e420f52586d5a1bb31
Reviewed-on: https://boringssl-review.googlesource.com/7620
Reviewed-by: David Benjamin <davidben@google.com>