Started adding some Server methods, adding some Util classes and adding a way to get the token from the Resource

src/OAuth2/Util/SecureKey.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace OAuth2\Util;
+
+class SecureKey
+{
+    public static function make($len = 42)
+    {
+        // We generate twice as many bytes here because we want to ensure we have
+        // enough after we base64 encode it to get the length we need because we
+        // take out the "/", "+", and "=" characters.
+        $bytes = openssl_random_pseudo_bytes($len * 2, $strong);
+
+        // We want to stop execution if the key fails because, well, that is bad.
+        if ($bytes === false || $strong === false) {
+            throw new Exception('Error Generating Key');
+        }
+
+        return substr(str_replace(['/', '+', '='], '', base64_encode($bytes)), 0, $len);
+    }
+}