lib: drop, fixes #16 (#37)

Hardware notes are seemingly less useful than a README, and
kernelAtLeast option, while potentially useful:

a) is not used anywhere in the tree at the moment,
b) doesn't properly work when there are multiple elements in the list,
c) assumes that there are no degradations ever.

lib/hardware-notes.nix

@@ -1,45 +0,0 @@
-{ config, lib, pkgs, ... }:
-
-with lib;
-
-let
-  # use tail recursion to prevent whitespace padding
-  mkLog = list:
-    let
-      head = builtins.head list;
-      tail = builtins.tail list;
-    in
-    ''
-      # ${head.title}
-      ${head.text}${if tail == [] then "" else "\n\n${mkLog tail}"}
-    '';
-in
-
-{
-
-  options = {
-    hardwareNotes = mkOption {
-      internal = true;
-      type = types.listOf types.optionSet;
-      options = {
-        title = mkOption {
-          type = types.str;
-          example = "Thunkpad-2000: increase self-destruct timeout";
-        };
-        text = mkOption {
-	  type = types.str;
-          example =
-            ''
-              Increase security timeout at boot using platform managment
-              tool to prevent premature data loss.
-            '';
-        };
-      };
-    };
-  };
-
-  config = {
-    environment.etc."hardware-notes".text = mkLog config.hardwareNotes;
-  };
-
-}

lib/kernel-version.nix

@@ -1,31 +0,0 @@
-{ config, lib, ... }:
-with lib;
-let
-  cfg = config;
-in
-{
-  options.kernelAtleast = mkOption {
-    type = types.listOf types.optionSet;
-    options =
-      [ { version = mkOption {
-            type = types.str;
-            example = "4.4";
-            description =
-              "Issue warning when kernel version is below this number.";
-          };
-          msg = mkOption {
-            type = types.str;
-            example = "";
-          };
-        }
-      ];
-  };
-
-  config.warnings = builtins.concatLists (map
-    (x: if (builtins.compareVersions cfg.boot.kernelPackages.kernel.version x.version) == -1
-        then [ "${x.msg} (${cfg.boot.kernelPackages.kernel.version} < ${x.version})" ]
-        else [ ]
-    ) cfg.kernelAtleast
-  );
-
-}