[Xmonad] darcs patch: make keyActions and buttonActions dynamically modifiable.

Hi all, Here's a small patch that breaks none of XMC, but allows us to easily write toggling keybindings. It also allows to remove keybinding dynamically, which also seems like a useful concept. It'll be more useful if we extend the map to also include help information, so we can present the user with a runtime summary of keybindings. But in any case, this patch by itself allows useful new functionality. I see little benefit in making the mouse bindings dynamically modifyable, but no harm either. And if we allow people to experiment with this, they may come up with something. David Thu Nov 8 08:04:23 PST 2007 David Roundy * make keyActions and buttonActions dynamically modifiable. This makes possible simple self-modifying toggle keybindings, the removal of keybindings, etc. Given that we were already storing a duplicate reference to these maps, I see no downside to allowing extensions to modify them.