adding a processor for basic git information

Adds the current Git Branch, and Git Commit key to the extra field

tests/Monolog/Processor/GitProcessorTest.php

@@ -0,0 +1,31 @@
+<?php
+
+/*
+ * This file is part of the Monolog package.
+ *
+ * (c) Jordi Boggiano <j.boggiano@seld.be>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Monolog\Processor;
+
+use Monolog\TestCase;
+
+class GitProcessorTest extends TestCase
+{
+    /**
+     * @covers Monolog\Processor\GitProcessor::__invoke
+     */
+    public function testProcessor()
+    {
+        $processor = new GitProcessor();
+        $record = $processor($this->getRecord());
+
+        $this->assertArrayHasKey('git', $record['extra']);
+
+        $this->assertTrue(!is_array($record['extra']['git']['branch']));
+        
+    }
+}