- add information abou the config file to the man page

- change so non-KLIBC builds under udev don't use /usr/include/sysfs,
  but instead use the sysfs included with udev (needs udev change and/or
  sysfsutils changes).

- do something with callout code - remove or change to a tag?

  This needs an implementation of a device specific callout or device
  specific code (called via some special  "tag" or such) before it can be
  completed. Someone with such hardware to send in a patch.
