Segregate lenovo/ subdir into thinkpad and ideapad directories

There are several significant differences between ThinkPads and the
other Lenovo models, so this structure must be more precise

lenovo/thinkpad/t460s.nix

@@ -0,0 +1,40 @@
+{ config, pkgs, ... }:
+
+{
+  imports =
+    [ ../lib/kernel-version.nix
+      ./general.nix
+    ];
+
+  ## BEGIN from generated hardware-configuration
+  ## Probably better to just use a freshly generated hardware.configuration.nix
+  ## than this, but including for reference.
+  # boot.initrd.availableKernelModules = [ "xhci_pci" "nvme" "usb_storage" "sd_mod" "rtsx_pci_sdmmc" ];
+  # boot.kernelModules = [ "kvm-intel" ];
+  # boot.extraModulePackages = [  ];
+  #
+  #
+  # nix.maxJobs = lib.mkDefault 4;
+  ## END from generated hardware-configuration
+
+  # Use the gummiboot efi boot loader. (From default generated configuration.nix)
+  boot.loader.systemd-boot.enable = true;
+  boot.loader.efi.canTouchEfiVariables = true;
+
+  # https://wiki.archlinux.org/index.php/Lenovo_ThinkPad_T460s
+  kernelAtleast = [
+    { version = "4.5.1"; msg = "The physical mouse buttons works incorrectly."; }
+    { version = "4.6";   msg = "Suspending the T460s by closing the lid when running on battery causes the machine to freeze up entirely."; }
+  ];
+
+  # For the screen. I don't know what to do with this information, but
+  # the hiDPI support is far from perfect (as of July 2016):
+
+  # Resolution: 2560 x 1440 px
+  # Size: 12.2" × 6.86" (30.99cm × 17.43cm)
+  # DPI: 209.8
+  # Dot Pitch: 0.1211mm
+  # Aspect Ratio: 16 × 9 (1.78:1)
+  # Pixel Count: 3,686,400
+  # Megapixels: 3.69MP
+}