bring iso builder in line with nixos
blue-installer: su binary got moved
mathijs/homedir: add bedup
pkgs.lib -> lib
latest ghc is 7.8.2
temp disable remmina: not compatible with freerdp 1.1
blue-installer: force using X11.

we include X11 packages anyway so we don't want to double up on
packages that have a non-X11 build as well.
fonts.extraFonts -> fonts.fonts
bash/zsh interaction changes
hardware.opengl.videoDrivers -> services.xserver.videoDrivers
nvidiafb module should be blacklisted on every system
bluescreen: blacklisting nouveau now happens automatically when nvidia driver is used
bluebook/mathijs: add texstudio and texmaker
mathijs/home: add agda's stdlib
node rethinkdb: fix latest version for native support