Add support for TLSv1.3
Created by: ikedas
This PR may add support for TLSv1.3 (RFC8446) for LDAP-related functions of Sympa.
Change:
- Corresponding parameters and command line arguments allow an additional option
tlsv1_3
.
Note:
- Actual support needs following components:
- OpenSSL library 1.1.1 or later
- IO-Socket-SSL 2.060 or later