Add readme

Author: einenlum

README.md

@@ -1,7 +1,56 @@
 # PHP Stack Detector
 
+This library allows to easily detect the PHP stack (Wordpress, Laravel, Symfony…) and the version used, when parsing a directory.
+
+Supported Stacks for now:
+
+- Wordpress
+- Laravel
+- Symfony
+- Statamic
+- Craft CMS
+
+## Install
+
+```
+composer require einenlum/php-stack-detector
+```
+
+## Usage
+
+```php
+<?php
+
+require_once __DIR__ . '/vendor/autoload.php';
+
+use Einenlum\PhpStackDetector\Detector;
+use Einenlum\PhpStackDetector\StackType;
+
+$detector = Detector::create();
+$stack = $detector->getStack('/path/to/a/symfony/directory');
+
+$stack->type === StackType===SYMFONY;
+$stack->version; // 5.4
+
+$stack = $detector->getStack('/path/to/an/unknown/symfony/version/directory');
+$stack->type === StackType===SYMFONY;
+$stack->version; // null
+
+$stack = $detector->getStack('/path/to/an/unknown/stack/directory');
+$stack; // null
+```
+
 ## Tests
 
 ```
-make test
+composer run test
 ```
+
+## Contribute
+
+Each stack has its own Detector implementing a [StackDetectorInterface](src/StackDetectorInterface.php).
+If the stack uses composer you can use the [PackageVersionProvider](src/Composer/PackageVersionProvider.php) class.
+
+You can add your own StackDetector and then add it to the `create` method of the [Detector](src/Detector.php).
+
+Any Pull Request welcome!