update docs

Author: cesargb

README.md

@@ -11,7 +11,19 @@ composer require descom/common
 ## Usage
 
 ```php
-$skeleton = new Descom\Skeleton\SkeletonClass;
+$finder = Symfony\Component\Finder\Finder::create()
+    ->in([
+        __DIR__.'/src',
+        __DIR__.'/tests',
+    ])
+    ->name('*.php')
+    ->notName('*.blade.php')
+    ->ignoreDotFiles(true)
+    ->ignoreVCS(true);
+
+return (new PhpCsFixer\Config())
+    ->setRules(Descom\Common\CsFixer::rules())
+    ->setFinder($finder);
 ```
 
 ## Testing