s_client: Show cert algorithms & validity period

s_client: Show cert algorithms & validity period

Add certificate validity period (v) and public key & signature algorithms (a) to the "Certificate Chain" output.

Eg:
Certificate chain
 0 s:C = US, ST = California, L = Mountain View, O = Google LLC, CN = www.google.com
   i:C = US, O = Google Trust Services, CN = GTS CA 1O1
   a:PKEY: id-ecPublicKey, 256 (bit); sigalg: RSA-SHA256
   v:NotBefore: Dec  3 14:49:26 2019 GMT; NotAfter: Feb 25 14:49:26 2020 GMT
 1 s:C = US, O = Google Trust Services, CN = GTS CA 1O1
   i:OU = GlobalSign Root CA - R2, O = GlobalSign, CN = GlobalSign
   a:PKEY: rsaEncryption, 2048 (bit); sigalg: RSA-SHA256
   v:NotBefore: Jun 15 00:00:42 2017 GMT; NotAfter: Dec 15 00:00:42 2021 GMT

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Dmitry Belyavskiy <beldmit@gmail.com>
(Merged from https://github.com/openssl/openssl/pull/10757)