Fix E_NOTICE emitted on empty response to INFO [section].

Empty responses can be returned when requesting an unsupported section
with the INFO command.

src/Command/ServerInfoV26x.php

@@ -22,7 +22,12 @@ class ServerInfoV26x extends ServerInfo
      */
     public function parseResponse($data)
     {
+        if ($data === '') {
+            return array();
+        }
+
         $info = array();
+
         $current = null;
         $infoLines = preg_split('/\r?\n/', $data);
 

tests/Predis/Command/ServerInfoV26xTest.php

@@ -291,6 +291,14 @@ BUFFER;
         $this->assertSame($expected, $this->getCommand()->parseResponse($raw));
     }
 
+    /**
+     * @group disconnected
+     */
+    public function testDoesNotEmitPhpNoticeOnEmptyResponse()
+    {
+        $this->assertSame(array(), $this->getCommand()->parseResponse(''));
+    }
+
     /**
      * @group connected
      */