Improve Makefile so that we don't install the original versions of patched
files in /etc/rc.d and /etc/sysconfig.
Split "readonly rootfs / tmpfs" parts of olpc patch into new 'readonly'
patch; plus add additional support for preserving changes to /etc/ssh,
/etc/sysconfig/i18n, /etc/timezone, /var/lib/dbus/machine-id, and
/var/lib/random-seed.
Add "pretty boot" support: bring up localhost before rhgb-client is
invoked; some additional calls to rhgb-client; move setsysfont from
rc.sysinit to z-boot-anim-stop (after animation has finished and DCON
is frozen); make sure that we cleanly exit pretty boot if interactive
boot mode is invoked.
