Added support for initialising encrypted disk

modules/common.nix

@@ -10,6 +10,20 @@
     canTouchEfiVariables = true;
   };
 
+  boot = {
+    loader = {
+      systemd-boot = {
+        enable = true;
+      };
+    };
+    efi = {
+      enable = true;
+      canTouchEfiVariables = true;
+      espDevice = "/dev/sda2";
+    };
+    initrd.luks.devices.cryptroot.device = "/dev/sda2";
+  }
+
   fileSystems."/" = {
     device = "/dev/mapper/root";
     fsType = "ext4";