[FEATURE REQ] Use extra mice buttons

[halr9000]

A lot of mice these days have at least 5 buttons. I use the back & fwd buttons (buttons 4 & 5) on my mouse all the time in Explorer to traverse directories. I also use it in Firefox (or IE if I must) to go back & forward in history. I'd like to do the same in Filezilla. Ideally the back button would change to the previous directory you were in, in the focused pane, and forward would go...forward.