Add encrypted my.cnf for MySQL 5.6+

MySQL 5.6 adds a utility called mysql_config_editor which allows you to encrypt my.cnf

See for more info:

• http://www.percona.com/blog/2014/11/25/more-secure-local-passwords-in-mysql-5-6-and-up/
• http://dev.mysql.com/doc/refman/5.6/en/mysql-config-editor.html