scripts/mkimage: set 'installer' as default boot option

some people dont enable "usb legacy support" in bios (or dont know how)
thus they can't access installer at all. live mode is non-important
fix compile on enabeld data-time check
fluxbox: disable xft/xpm/fribidi. not used anyway
fluxbox: avoid potential SIGFPE in Menu::updateMenu()
busybox (initramfs): add 'ping' and 'ether-wake' applet
init: added wake-on-lan script
config/optimize: dont build with '-ffast-math'

Signed-off-by: Stephan Raue <stephan@openelec.tv>