Allow changing the connection of a buffer without first closing it

[kyhung]

To allow running the same set of SQL statments with different DB connections, say Local / Testing. Currently I need to first close the buffer, reopen it and call DBUIFindBuffer in order to attach it to another connection.
It will be convenient if there is a command say DBUISwitchBufferConn for user to attach the current buffer to another connection.

Thank you