introduce classes for token list and token types

lib/TokenPostcode.php

@@ -0,0 +1,31 @@
+<?php
+
+namespace Nominatim\Token;
+
+/**
+ * A postcode token.
+ */
+class Postcode
+{
+    public $iId;
+    // full postcode
+    public $sPostcode;
+    // optional restriction to a given country
+    public $sCountryCode;
+
+    public function __construct($iId, $sPostcode, $sCountryCode = '')
+    {
+        $this->iId = $iId;
+        $this->sPostcode = $sPostcode;
+        $this->sCountryCode = empty($sCountryCode) ? '' : $sCountryCode;
+    }
+
+    public function debugInfo()
+    {
+        return array(
+                'ID' => $this->iId,
+                'Type' => 'postcode',
+                'Info' => $this->sPostcode.'('.$this->sCountryCode.')'
+               );
+    }
+}