Add git config and initial emacs config.

nix/configuration/roles/git/default.nix

@@ -0,0 +1,15 @@
+{ config, lib, pkgs, ... }:
+
+{
+  imports = [];
+
+  environment.systemPackages = with pkgs; [
+    git
+  ];
+
+  home-manager.users.talexander = { pkgs, ... }: {
+    home.file.".gitconfig" = {
+      source = ./files/gitconfig_home;
+    };
+  };
+}