Apply CS fixes and refactor GridFS classes

Author: jmikola

src/Exception/GridFSFileNotFoundException.php

@@ -4,7 +4,8 @@
 
 class GridFSFileNotFoundException extends \MongoDB\Driver\Exception\RuntimeException implements Exception
 {
-	public function __construct($fname, $nameSpace){
-        parent::__construct(sprintf('Unable to find file by: %s in %s', $fname,$nameSpace));
-	}
+    public function __construct($filename, $namespace)
+    {
+        parent::__construct(sprintf('Unable to find file "%s" in namespace "%s"', $filename, $namespace));
+    }
 }