Add basic usage example and benefits list

Author: ekvedaras

README.md

@@ -1,5 +1,54 @@
 # PHP Enum
 
-![run-tests](https://github.com/ekvedaras/php-enum/workflows/run-tests/badge.svg)
+[![Software License](https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat)](LICENSE)
+[![Latest Version on Packagist](https://img.shields.io/packagist/v/ekvedaras/php-enum.svg?style=flat)](https://packagist.org/packages/ekvedaras/php-enum)
+[![Total Downloads](https://img.shields.io/packagist/dt/ekvedaras/php-enum.svg?style=flat)](https://packagist.org/packages/ekvedaras/php-enum)
+![Tests](https://github.com/ekvedaras/php-enum/workflows/run-tests/badge.svg)
 
-PHP enum implementation
+Original idea taken from [happy-types/enumerable-type](https://packagist.org/packages/happy-types/enumerable-type), so take a look, it may suit your needs better.
+This package adds `meta` field, provides a few more methods like `options`, `keys`, `json`, etc. 
+and there are `array` and illuminate `collection` implementations to choose from. 
+
+## Benefits
+
+* Enums in general allow to avoid [magic values](https://en.wikipedia.org/wiki/Magic_number_(programming)#Unnamed_numerical_constants)
+* By type hinting forces only allowed values to be passed to methods (or returned)
+* Easy way to list all possible values
+* More feature rich and flexible then other enum implementations
+* IDE friendly, so auto complete, usage analysis and refactorings all work
+
+## Usage
+
+Create enums by extending either `EKvedaras\PHPEnum\PHPArray\Enum` or `EKvedaras\PHPEnum\Illuminate\Collection\Enum`.
+
+```php
+<?php
+
+use EKvedaras\PHPEnum\PHPArray\Enum;
+
+class PaymentStatus extends Enum {
+    /**
+     * @return static
+     */
+    final public static function pending(): self
+    {
+        return static::get('pending', 'Payment is pending');
+    }
+
+    /**
+     * @return static
+     */
+    final public static function completed(): self
+    {
+        return static::get('completed', 'Payment has been processed');
+    }
+    
+    /**
+     * @return static
+     */
+    final public static function failed(): self
+    {
+        return static::get('failed', 'Payment has failed');
+    }
+}
+```