change README and add CHANGELOG

Author: a-afsharfarnia

CHANGELOG.md

@@ -0,0 +1,9 @@
+# Changelog for github.com/a-afsharfarnia/php-data-mapper
+
+All notable changes to this package will be documented in this file.
+The format is based on [Keep a Changelog](http://keepachangelog.com/)
+and this project adheres to [Semantic Versioning](http://semver.org/).
+
+## [1.0.0] - 2019-10-21
+
+First release

README.md

@@ -1,14 +1,37 @@
 # A Simple Method to Make a Data Mapper in PHP
-In most projects, we have to map data to other cases. For example we want to map `1m` to `1 minute` or `3d` to `3 days`.
-
-This package is a data mapper and we can create our mapper based on that very easily.
+By this package we can map data from one to another. For example we can create a time mapper for map `1m` to `1 minute` and vise versa, or map `3d` to `3 days`. Thereby when we have `1m`, we will be able to reach `1 minute` and so on.
 
 ## Install
  ```
   $ composer require a-afsharfarnia/data-mapper
  ```
 
 ### How to use 
-You can find samples of using this package in `/src/samples`. You can have a look on `TimeMapper` and `LanguageMapper` classes.
+After installing the package, the only thing you have to do is creating your mapper classes. Imagine you want to have following mappers in your projects:
+
+- Time Mapper (e.g. map `1m` to `1 minute` and vise versa)
+- Language Mapper (e.g. map `en` to `english` and vise versa)
+
+So, you must create a class for each mapper. You can have a look on `TimeMapper` and `LanguageMapper` classes as a sample in `/src/samples`.
+
+As you can see in samples, each mapper class is extended of `Afsharfarnia\DataMapper\mappers\Mapper`. Then in each mapper class you must define a `$mapper` static property which includes mapper data.
+
+``` php
+    public static $mapper = [
+        "1m" => "1minute",
+        "30m" => "30minutes",
+        "1h" => "1hour",
+        "8h" => "8hours",
+        "12h" => "12hours",
+        "1d" => "1day",
+        "3d" => "3days",
+        "1w" => "1week",
+        "1M" => "1month"
+    ];
+```
 
-In fact, in your project, for each map data, you must create a class which is extended of `Afsharfarnia\DataMapper\mappers\Mapper` of this package. Then in each class you must define a `$mapper` static property which includes its mapper data. 
+After creating your mapper classes, you can use them in your projects as following:
+```php
+    echo TimeMapper::mapData("1m");               --> result: 1 minute   (to map)
+    echo TimeMapper::unmapData("12hours");        --> result: 12h        (to unmap)
+```