common: move to modules, move some files out, modules: adjust dir structure

modules/nixos/programs/ssh.nix

@@ -0,0 +1,26 @@
+{ config, pkgs, ... }:
+
+{
+  programs.ssh = {
+    startAgent = true;
+    enableAskPassword = true;
+    extraConfig = "
+      IdentityFile /home/wo2w/.ssh/ssh-key
+      User wo2w
+      Host gameserver
+        Hostname 192.168.2.221
+        Port 22
+      Host Swordsmachine
+        Hostname 192.168.2.84
+        Port 8743
+      Host Earthmover
+        Hostname 192.168.2.87
+        Port 8743
+    ";
+  };
+
+  environment = {
+    systemPackages = if config.services.desktopManager.plasma6.enable then with pkgs; [ kdePackages.ksshaskpass ] else [];
+    variables.SSH_ASKPASS_REQUIRE = "prefer";
+  };
+}