add readme

README.md

@@ -4,7 +4,9 @@
 [![codecov](https://codecov.io/gh/formal-php/migrations/branch/develop/graph/badge.svg)](https://codecov.io/gh/formal-php/migrations)
 [![Type Coverage](https://shepherd.dev/github/formal-php/migrations/coverage.svg)](https://shepherd.dev/github/formal-php/migrations)
 
-Description
+This library is a simple one way migration system.
+
+You can run both SQL and Commands migrations.
 
 ## Installation
 
@@ -14,4 +16,30 @@ composer require formal/migrations
 
 ## Usage
 
-Todo
+```php
+use Formal\Migrations\Factory;
+use Innmind\OperatingSystem\Factory as OS;
+use Innmind\Url\{
+    Url,
+    Path,
+};
+
+$dsn = Url::of('mysql://user:[email protected]:3306/database');
+
+Factory::of(OS::build())
+    ->storeVersionsInDatabase($dsn)
+    ->sql()
+    ->files(Path::of('migrations/folder/'))
+    ->migrate($dsn)
+    ->match(
+        static fn() => print('Everything has been migrated'),
+        static fn(\Throwable $error) => printf(
+            'Migrations failed with the message : %s',
+            $error->getMessage(),
+        ),
+    );
+```
+
+## Documentation
+
+Full documentation available [here](https://formal-php.github.io/migrations/).