Added exception interface

Author: GrahamCampbell

lib/Gitlab/Exception/ErrorException.php

@@ -5,6 +5,6 @@
  *
  * @author Joseph Bielawski <stloyd@gmail.com>
  */
-class ErrorException extends \ErrorException
+class ErrorException extends \ErrorException implements ExceptionInterface
 {
 }

lib/Gitlab/Exception/ExceptionInterface.php

@@ -0,0 +1,12 @@
+<?php namespace Gitlab\Exception;
+
+use Http\Client\Exception;
+
+/**
+ * ExceptionInterface
+ *
+ * @author Graham Campbell <graham@alt-three.com>
+ */
+interface ExceptionInterface extends Exception
+{
+}

lib/Gitlab/Exception/InvalidArgumentException.php

@@ -5,6 +5,6 @@
  *
  * @author Joseph Bielawski <stloyd@gmail.com>
  */
-class InvalidArgumentException extends \InvalidArgumentException
+class InvalidArgumentException extends \InvalidArgumentException implements ExceptionInterface
 {
 }

lib/Gitlab/Exception/MissingArgumentException.php

@@ -5,7 +5,7 @@
  *
  * @author Joseph Bielawski <stloyd@gmail.com>
  */
-class MissingArgumentException extends ErrorException
+class MissingArgumentException extends ErrorException implements ExceptionInterface
 {
     public function __construct($required, $code = 0, $previous = null)
     {

lib/Gitlab/Exception/RuntimeException.php

@@ -5,6 +5,6 @@
  *
  * @author Joseph Bielawski <stloyd@gmail.com>
  */
-class RuntimeException extends \RuntimeException
+class RuntimeException extends \RuntimeException implements ExceptionInterface
 {
 }

lib/Gitlab/Exception/ValidationFailedException.php

@@ -5,6 +5,6 @@
  *
  * @author Joseph Bielawski <stloyd@gmail.com>
  */
-class ValidationFailedException extends ErrorException
+class ValidationFailedException extends ErrorException implements ExceptionInterface
 {
 }