#130 Should send right-click to apps

[Egmont Koblinger]

Roxterm doesn't send right-click events to application that are interested in mouse events. E.g. you can't use it to toggle a file in midnight commander.

If an app is interested in mouse events, Roxterm should send it right-click events instead of presenting the context menu. The context menu could still be popped up if let's say a modifier key is also pressed.

See https://bugzilla.gnome.org/show_bug.cgi?id=13299#c34 for how gnome-terminal does this.