support SSH tunnel access to MySQL server

[mappu]

Hi, A lot of MySQL servers are only accessible via SSH tunnels. It would be good to support MySQL over SSH tunnel in the connection manager. Thanks

[mohag]

It might be useful for all database types that use TCP connections. (Single TCP connection ones are easier...) (Even forcing the user to manually configure the ports to be tunneled might work better than not having the option)

(This is why I'm currently using MySQL Workbench for my uses. I do have some other non-MySQL stuff that I want to connect to as well)