Add description to README.md

Author: devanych

README.md

@@ -1,3 +1,96 @@
 # HTTP Request
 
-The repository is under development, and the description will appear later.
+[![License](https://poser.pugx.org/httpsoft/http-request/license)](https://packagist.org/packages/httpsoft/http-request)
+[![Latest Stable Version](https://poser.pugx.org/httpsoft/http-request/v)](https://packagist.org/packages/httpsoft/http-request)
+[![Total Downloads](https://poser.pugx.org/httpsoft/http-request/downloads)](https://packagist.org/packages/httpsoft/http-request)
+[![GitHub Build Status](https://github.com/httpsoft/http-request/workflows/build/badge.svg)](https://github.com/httpsoft/http-request/actions)
+[![Scrutinizer Code Coverage](https://scrutinizer-ci.com/g/httpsoft/http-request/badges/coverage.png?b=master)](https://scrutinizer-ci.com/g/httpsoft/http-request/?branch=master)
+[![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/httpsoft/http-request/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/httpsoft/http-request/?branch=master)
+
+This package implements [Psr\Http\Message\RequestInterface](https://github.com/php-fig/http-message/blob/master/src/RequestInterface.php) and [Psr\Http\Message\ServerRequestInterface](https://github.com/php-fig/http-message/blob/master/src/ServerRequestInterface.php) from [PSR-7 HTTP Message](https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-7-http-message.md) in accordance with the [RFC 7230](https://tools.ietf.org/html/rfc7230) and [RFC 7231](https://tools.ietf.org/html/rfc7231) specifications.
+
+## Documentation
+
+* [In English language](https://httpsoft.org/docs/request).
+* [In Russian language](https://httpsoft.org/ru/docs/request).
+
+## Installation
+
+This package requires PHP version 7.4 or later.
+
+```
+composer require httpsoft/http-request
+```
+
+## Usage Request
+
+```php
+use HttpSoft\Request\Request;
+use HttpSoft\Request\RequestFactory;
+
+$request = new Request('POST', 'http://example.com', 'data://,Content', ['Content-Type' => 'text/html'], '2');
+// Or using the factory:
+$request = RequestFactory::create(
+    'POST', // Request method
+    'https://example.com', // Request URI
+    'data://,Content', // HTTP message body
+    ['Content-Type' => 'text/html' /* Other headers */],
+    '2' // HTTP protocol version
+);
+
+$request->getMethod(); // 'POST'
+$request->getProtocolVersion(); // '2'
+$request->getBody()->getContents(); // 'Content'
+(string) $request->getUri(); // 'https://example.com/path'
+$request->getHeaders(); // ['Host' => ['example.com'], 'Content-Type' => ['text/html']]
+```
+
+## Usage ServerRequest
+
+```php
+use HttpSoft\Request\ServerRequest;
+use HttpSoft\Request\ServerRequestFactory;
+
+$request = new ServerRequest(
+    $_SERVER,
+    $_FILES,
+    $_COOKIE,
+    $_GET,
+    $_POST,
+    'GET', // Request method
+    'https://example.com', // Request URI
+    'php://input', // HTTP message body
+    [/* Headers */],
+    '2' // HTTP protocol version
+);
+// Or using the factory (all necessary data will be received automatically):
+$request = ServerRequestFactory::createFromGlobals($_SERVER, $_FILES, $_COOKIE, $_GET, $_POST);
+// equivalently to:
+$request = ServerRequestFactory::createFromGlobals();
+// equivalently to:
+$request = ServerRequestFactory::create();
+
+$request->getMethod(); // 'GET'
+$request->getProtocolVersion(); // '2'
+$request->getBody()->getContents(); // ''
+(string) $request->getUri(); // 'https://example.com'
+$request->getHeaders(); // ['Host' => ['example.com']]
+$request->getServerParams(); // $_SERVER
+$request->getUploadedFiles(); // $_FILES
+$request->getCookieParams(); // $_COOKIE
+$request->getQueryParams(); // $_GET
+$request->getParsedBody(); // $_POST
+$request->getAttributes(); // []
+```
+
+By default [HttpSoft\Request\SapiNormalizer](https://github.com/httpsoft/http-request/blob/master/src/SapiNormalizer.php) is used for normalization of server parameters. You can use your own server parameters normalizer, for this you need to implement an [HttpSoft\Request\ServerNormalizerInterface](https://github.com/httpsoft/http-request/blob/master/src/ServerNormalizerInterface.php) interface.
+
+```php
+$normalizer = new YouCustomServerNormalizer();
+
+$request = ServerRequestFactory::create($normalizer);
+// equivalently to:
+$request = ServerRequestFactory::createFromGlobals($_SERVER, $_FILES, $_COOKIE, $_GET, $_POST, $normalizer);
+// or with custom superglobals
+$request = ServerRequestFactory::createFromGlobals($server, $files, $cookie, $get, $post, $normalizer);
+```