Missing provider class

Signed-off-by: Alex Bilbie <alex@alexbilbie.com>

src/Oauth2/Client/Provider.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace OAuth2\Client;
+
+class Provider
+{
+	private function __constuct() {}
+
+	public static function factory($name, array $options = null)
+	{
+		if ( ! class_exists($name)) {
+
+			throw new OAuth2\Client\Exception('There is no identity provider called: '.$name);
+
+		}
+
+		return new $name($options);
+	}
+}