Update intro.md
Update intro.md

translate for 01-overview/master-slave
apache/incubator-shardingsphere,apache/incubator-shardingsphere,leeyazhou/sharding-jdbc,apache/incubator-shardingsphere,leeyazhou/sharding-jdbc,apache/incubator-shardingsphere,leeyazhou/sharding-jdbc,leeyazhou/sharding-jdbc