Closes #1866. Thanks to roebotron.

The `tls_version` option now defines the *minimum* TLS protocol version to
be used, rather than the exact version.

Closes #1258. Thanks to Daniele Sluijters.

Closes #1311. Thanks to beville.

Closes #265.

Closes #1862. Thanks to Kaushik-27.

This happens when an unhandled error occurs on a socket/read write. The
message is confusing to people.

Signed-off-by: raspopov <raspopov@cherubicsoft.com>

Signed-off-by: raspopov <raspopov@cherubicsoft.com>

<arpa/inet.h> header is required to compile this source. Without it, WARNING is generated.

mosquitto/lib/socks_mosq.c: In function 'socks5__send':
mosquitto/lib/socks_mosq.c:156:22: warning: implicit declaration of function 'inet_pton' [-Wimplicit-function-declaration]
   ipv4_pton_result = inet_pton(AF_INET, mosq->host, &addr_ipv4);

Signed-off-by: ChangJoon Lee <changjoon.lee@lge.com>

This converts password_file and acl_file checks to act like a v5 plugin.