Update install script, add pine stub

install.sh

@@ -1,16 +1,22 @@
 #!/usr/bin/env bash
 
-machine=$1
+dest=$1
+machine=$HOSTNAME
+
+if [[ -z "$dest" ]]; then
+    dest="/etc/nixos/configuration.nix"
+fi
 
 if [[ -z "$machine" ]]; then
-    machine=$(hostname)
+    machine=default-name
 fi
 
-if [[ ! -d "machines/$machine" ]]; then
+if [[ ! -d "machines/$machine" || ! -f "machines/$machine/configuration.nix" ]]; then
     echo "$machine is not a known machine"
+    echo "Run as \`env HOSTNAME=<MACHINE> ./install.sh\` to override."
     exit
 else
-    echo "Linking ./machines/$machine/configuration.nix to /etc/nixos/configuration.nix"
+    echo "Linking ./machines/$machine/configuration.nix to $dest"
 fi
 
-sudo ln -sf $PWD/machines/$machine/configuration.nix /etc/nixos/configuration.nix
+sudo ln -sf $PWD/machines/$machine/configuration.nix $dest

machines/pine/configuration.nix

@@ -0,0 +1 @@
+TODO