Fix dead links (#131)

Author: kamil-tekiela

entities/global.ent

@@ -284,9 +284,8 @@
 <!ENTITY url.mysql.docs.date "http://dev.mysql.com/doc/mysql/en/date-and-time-functions.html">
 <!ENTITY url.mysql.docs.document-store "https://dev.mysql.com/doc/refman/8.0/en/document-store.html">
 <!ENTITY url.mysql.docs.error "http://dev.mysql.com/doc/mysql/en/error-handling.html">
-<!ENTITY url.mysql.docs.memcached "http://dev.mysql.com/doc/en/ha-memcached.html">
-<!ENTITY url.mysql.docs.refresh "http://dev.mysql.com/doc/mysql/en/mysql-refresh.html">
-<!ENTITY url.mysql.docs.ssl.set "http://dev.mysql.com/doc/mysql/en/mysql-ssl-set.html">
+<!ENTITY url.mysql.docs.refresh "https://dev.mysql.com/doc/c-api/8.4/en/mysql-refresh.html">
+<!ENTITY url.mysql.docs.ssl.set "https://dev.mysql.com/doc/c-api/8.4/en/mysql-ssl-set.html">
 <!ENTITY url.mysql.docs.ssl.using "https://dev.mysql.com/doc/en/using-encrypted-connections.html">
 <!ENTITY url.mysql.docs.stmt-attr-set "http://dev.mysql.com/doc/en/mysql-stmt-attr-set.html">
 <!ENTITY url.mysql.docs.replication "http://dev.mysql.com/doc/mysql/en/replication.html">