ZAxisMapping causing trouble

[Kean Johnston]

> No, please let the default setting. Mouse button events 4 + 5 are the
> default buttons understood by applications for mouse wheels.
The problem with teh way things were is that the default string
was overriding the os-support layers ability to correctly map
the buttons. Also, it was setting the default in the wrong place.
I have no issue with teh configuration code writing out a default
entry to the xorg.conf file, but the way things were, if you removed
the ZAxisMapping line from that file, presumably becuase it was
causing trouble, then having that default string would re-instate
the settings behind your back, and in fact there ends up being no
way to get rid of it.

Kean