Update links to OpenSSL docs

Author: jacekwegr

doc/configuration/outgoing-connections.md

@@ -414,7 +414,7 @@ Password to the X509 PEM file with the private key.
 * **Default:** not set, all supported cipher suites are accepted
 * **Example:** `tls.ciphers = "ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384"`
 
-Cipher suites to use. Please refer to the [OpenSSL documentation](http://www.openssl.org/docs/man1.0.2/apps/ciphers.html) for the cipher string format. For allowed values, see the [Erlang/OTP SSL documentation](https://erlang.org/doc/man/ssl.html#type-ciphers).
+Cipher suites to use. Please refer to the [OpenSSL documentation](https://docs.openssl.org/master/man1/openssl-ciphers/) for the cipher string format. For allowed values, see the [Erlang/OTP SSL documentation](https://erlang.org/doc/man/ssl.html#type-ciphers).
 
 ### `outgoing_pools.*.*.connection.tls.versions`
 * **Syntax:** list of strings

doc/configuration/s2s.md

@@ -84,7 +84,7 @@ This option defines IP addresses and port numbers for specific non-local XMPP do
 * **Example:** `ciphers = "TLSv1.2"`
 
 Defines a list of accepted SSL ciphers for outgoing S2S connections.
-Please refer to the [OpenSSL documentation](http://www.openssl.org/docs/apps/ciphers.html) for the cipher string format.
+Please refer to the [OpenSSL documentation](https://docs.openssl.org/master/man1/openssl-ciphers/) for the cipher string format.
 
 ### `s2s.max_retry_delay`
 * **Syntax:** positive integer

doc/listeners/listen-c2s.md

@@ -136,7 +136,7 @@ Path to the Diffie-Hellman parameter file.
 * **Default:** for `fast_tls` the default is`"TLSv1.2:TLSv1.3"`. For `just_tls` this option is not set by default - all supported suites are accepted.
 * **Example:** `tls.ciphers = "ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384"`
 
-Cipher suites to use with StartTLS or TLS. Please refer to the [OpenSSL documentation](http://www.openssl.org/docs/man1.0.2/apps/ciphers.html) for the cipher string format. For `fast_tls`, this string can be used to specify versions as well. For `just_tls`, see the [Erlang/OTP SSL documentation](https://erlang.org/doc/man/ssl.html#type-ciphers) for allowed values.
+Cipher suites to use with StartTLS or TLS. Please refer to the [OpenSSL documentation](https://docs.openssl.org/master/man1/openssl-ciphers/) for the cipher string format. For `fast_tls`, this string can be used to specify versions as well. For `just_tls`, see the [Erlang/OTP SSL documentation](https://erlang.org/doc/man/ssl.html#type-ciphers) for allowed values.
 
 ### `listen.c2s.tls.protocol_options` - only for `fast_tls`
 * **Syntax:** array of strings

doc/modules/mod_global_distrib.md

@@ -235,7 +235,7 @@ These options will be passed to the `fast_tls` driver.
 * **Default:** `"TLSv1.2:TLSv1.3"`
 * **Example:** `ciphers = "ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384"`
 
-Cipher suites to use with StartTLS or TLS. Please refer to the [OpenSSL documentation](https://www.openssl.org/docs/man1.0.2/man1/ciphers.html) for the cipher string format.
+Cipher suites to use with StartTLS or TLS. Please refer to the [OpenSSL documentation](https://docs.openssl.org/master/man1/openssl-ciphers/) for the cipher string format.
 
 #### `modules.mod_global_distrib.connections.tls.dhfile`
 * **Syntax:** string, path in the file system