lib-ssl-iostream: Add accessors for additional SSL protocol details This is needed in order to send these details as fields to auth process

lib-ssl-iostream: Add io_stream_ssl_global_init()

lib-ssl-iostream: Add TLS SNI callback and a way to change SSL context

lib-ssl-iostream: ssl_iostream_cert_match_name() - add reason_r parameter The callers were also changed to add the reason to error messages.

lib-ssl-iostream: ssl_iostream_cert_match_name() - Change to return bool The return value makes much more sense as a boolean TRUE/FALSE than 0/-1.

lib-ssl-iostream: Add ssl_iostream_settings_drop_stream_only()

lib-ssl-iostream: Add ssl_iostream_settings_equals()

lib-ssl-iostream: Add refcounting to ssl_iostream_context

lib-ssl-iostream: Add get_compression accessor This is needed by login-common

lib-ssl-iostream: Use more standard _init() & _deinit() to initialize SSL plugin This is mainly to make it easier for test programs to link to the plugin directly.

dovecot: Remove ssl-params

lib-ssl-iostream: Added dh_length parameter to ssl_iostream_generate_params() This is an API change, but nobody was actually using this function.

lib-ssl-iostream: Deinitialization fixes.

lib-ssl-iostream: Added ssl_iostream_has_handshake_failed()

lib-ssl-iostream: Added support for TLS SNI, which caused some API changes.

lib-ssl-iostream: ssl_iostream_set_handshake_callback() API changed. The callback can now return the error message to caller instead of having to log it itself.

lib-ssl-iostream: API changes to return error strings if init() functions fail. This also fixed a couple of broken error handlings.

lib-ssl-iostream now dynamically loads openssl library instead of linking to it. This allowed removing the separate libdovecot-ssl library. In future if GnuTLS/NSS support is added it would also allow switching between them dynamically.