Add description to README.md

Author: devanych

README.md

@@ -1,3 +1,98 @@
 # HTTP Response
 
-The repository is under development, and the description will appear later.
+[![License](https://poser.pugx.org/httpsoft/http-response/license)](https://packagist.org/packages/httpsoft/http-response)
+[![Latest Stable Version](https://poser.pugx.org/httpsoft/http-response/v)](https://packagist.org/packages/httpsoft/http-response)
+[![Total Downloads](https://poser.pugx.org/httpsoft/http-response/downloads)](https://packagist.org/packages/httpsoft/http-response)
+[![GitHub Build Status](https://github.com/httpsoft/http-response/workflows/build/badge.svg)](https://github.com/httpsoft/http-response/actions)
+[![Scrutinizer Code Coverage](https://scrutinizer-ci.com/g/httpsoft/http-response/badges/coverage.png?b=master)](https://scrutinizer-ci.com/g/httpsoft/http-response/?branch=master)
+[![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/httpsoft/http-response/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/httpsoft/http-response/?branch=master)
+
+This package contains a collection of classes that implements [Psr\Http\Message\ResponseInterface](https://github.com/php-fig/http-message/blob/master/src/ResponseInterface.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/response).
+* [In Russian language](https://httpsoft.org/ru/docs/response).
+
+## Installation
+
+This package requires PHP version 7.4 or later.
+
+```
+composer require httpsoft/http-response
+```
+
+## Usage Response
+
+```php
+use HttpSoft\Response\Response;
+use HttpSoft\Response\ResponseFactory;
+
+$response = ResponseFactory::create();
+// equivalently to:
+$response = new Response();
+// default values
+$response->getStatusCode(); // 200
+$response->getReasonPhrase(); // 'OK'
+$response->getBody()->getContents(); // ''
+$response->getBody()->getMetadata('uri') // 'php://temp'
+$response->getHeaders(); // []
+$response->getProtocolVersion(); // '1.1'
+
+// Create with the passed parameters
+$response = new Response(404, '', 'php://memory', ['Content-Language' => 'en'], '2');
+$response->getStatusCode(); // 404
+$response->getReasonPhrase(); // 'Not Found'
+$response->getBody()->getContents(); // ''
+$response->getBody()->getMetadata('uri') // 'php://memory'
+$response->getHeaders(); // ['Content-Language' => ['en']]
+$response->getProtocolVersion(); // '2'
+
+// Write to the response body:
+$response->getBody()->write('Content');
+$response->getBody()->getContents(); // 'Content'
+
+// With `Content-Type` header:
+$newResponse = $response->withHeader('Content-Type', 'text/plain');
+$newResponse->getHeaderLine('content-type'); // 'text/plain'
+$newResponse->getHeaders(); // ['Content-Language' => ['ru'], 'Content-Type' => ['text/plain']]
+
+// With status code:
+$newResponse = $response->withStatus(Response::STATUS_INTERNAL_SERVER_ERROR);
+$newResponse->getStatusCode(); // 500
+$newResponse->getReasonPhrase(); // 'Internal Server Error'
+
+// With status code and reason phrase:
+$newResponse = $response->withStatus(599, 'Custom Phrase');
+$newResponse->getStatusCode(); // 599
+$newResponse->getReasonPhrase(); // 'Custom Phrase'
+```
+
+## Create custom responses
+
+```php
+// Create `Psr\Http\Message\ResponseInterface` instance from HTML: 
+$response = new HttpSoft\Response\HtmlResponse('<p>HTML</p>');
+$response->getHeaderLine('content-type'); // 'text/html; charset=UTF-8'
+
+// Create `Psr\Http\Message\ResponseInterface` instance from data to convert to JSON: 
+$response = new HttpSoft\Response\JsonResponse(['key' => 'value']);
+$response->getHeaderLine('content-type'); // 'application/json; charset=UTF-8'
+
+// Create `Psr\Http\Message\ResponseInterface` instance from Text: 
+$response = new HttpSoft\Response\TextResponse('Text');
+$response->getHeaderLine('content-type'); // 'text/plain; charset=UTF-8'
+
+// Create `Psr\Http\Message\ResponseInterface` instance from XML: 
+$response = new HttpSoft\Response\XmlResponse('<xmltag>XML</xmltag>');
+$response->getHeaderLine('content-type'); // 'application/xml; charset=UTF-8'
+
+// Create `Psr\Http\Message\ResponseInterface` instance for redirect: 
+$response = new HttpSoft\Response\RedirectResponse('https/example.com');
+$response->getHeaderLine('location'); // 'https/example.com'
+
+// Create `Psr\Http\Message\ResponseInterface` instance for empty response: 
+$response = new HttpSoft\Response\EmptyResponse();
+$response->getStatusCode(); // 204
+$response->getReasonPhrase(); // 'No Content'
+```