enables eeze_udev support where available, currently only illume2, as a device backend to replace ehal.
unless --enable-device-udev is explicitly specified, e will continue to use ehal as the device backend.
upon selection of eeze_udev, a brief warning will be shown during config summary.
components that do not support eeze_udev will still fall back to hal even if eeze_udev is selected
SVN revision: 48867