It seems that the installation path for chez modules no longer includes
the Chez version. This fixes the build for chez-mit and chez-scmutils.

…pendency

chez-modules: Fix path to csv-site.

rgp: 1.7.0.29 -> 1.8

pythonPackages.holidays: fix build by adding korean-lunar-calendar dependency

airscan: 0.99.8 -> 0.99.16

Regression introduced by 053b05d.

The commit in question essentially removed the "with pkgs;" from the
scope around the various packages added to environment.systemPackages.

Since services.colord.enable and services.xserver.wacom.enable are false
by default, the change above didn't directly result in an evaluation
error.

Tested evaluation before and after this change via:

  for cfg in hardware.bluetooth.enable \
             networking.networkmanager.enable \
             hardware.pulseaudio.enable \
             powerManagement.enable \
             services.colord.enable \
             services.samba.enable \
             services.xserver.wacom.enable; do
    nix-instantiate --eval nixos --arg configuration '{
      services.xserver.desktopManager.plasma5.enable = true;
      '"$cfg"' = true;
    }' -A config.environment.systemPackages > /dev/null
  done

Signed-off-by: aszlig <aszlig@nix.build>
Cc: @ttuegel