Add missing simple test for authentication with Client::AUTH_URL_CLIENT_ID, extended Travis-CI testing

Author: stloyd

.travis.yml

@@ -1,11 +1,13 @@
 language: php
 
 php:
+  - 5.3.3
   - 5.3
   - 5.4
+  - 5.5
 
 before_script:
-  - composer install --dev
+  - composer install --dev --prefer-source
 
 script:
   - phpunit --coverage-text

test/Github/Tests/ClientTest.php

@@ -55,6 +55,17 @@ public function shouldAuthenticateUsingUrlToken()
         $this->assertInstanceOf('Github\HttpClient\HttpClient', $client->getHttpClient());
     }
 
+    /**
+     * @test
+     */
+    public function shouldAuthenticateUsingUrlClientId()
+    {
+        $client = new Client();
+        $client->authenticate('client_id', 'client_secret', Client::AUTH_URL_CLIENT_ID);
+
+        $this->assertInstanceOf('Github\HttpClient\HttpClient', $client->getHttpClient());
+    }
+
     /**
      * @test
      */