Updated README

Author: ondrejmirtes

README.md

@@ -2,3 +2,20 @@
 
 * [PHPStan](https://github.com/phpstan/phpstan)
 * [Dibi](https://dibiphp.com/)
+
+This extension defines dynamic methods on `Dibi\Fluent` instance. They are called to build an SQL query dynamically.
+
+## Usage
+
+To use this extension, require it in [Composer](https://getcomposer.org/):
+
+```
+composer require phpstan/phpstan-dibi
+```
+
+And include extension.neon in your project's PHPStan config:
+
+```
+includes:
+	- vendor/phpstan/phpstan-dibi/extension.neon
+```