Consolidate documentation to README.md

Signed-off-by: Michal Čihař <michal@cihar.com>

README.md

@@ -5,3 +5,31 @@ ShapeFile library for PHP
 [![codecov.io](https://codecov.io/github/phpmyadmin/shapefile/coverage.svg?branch=master)](https://codecov.io/github/phpmyadmin/shapefile?branch=master)
 [![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/phpmyadmin/shapefile/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/phpmyadmin/shapefile/?branch=master)
 [![Packagist](https://img.shields.io/packagist/dt/phpmyadmin/shapefile.svg)](https://packagist.org/packages/phpmyadmin/shapefile)
+
+## Features
+
+Curretntly the 2D variants of the ShapeFile format as defined in
+http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf. The library
+currently supports reading and editing of ShapeFiles and the Associated
+information (DBF file). There are a lot of things that can be improved in the
+code, if you are interested in developing, helping with the documentation,
+making translations or offering new ideas please contact us.
+
+## Installation
+
+Please use [Composer][1] to install:
+
+``` 
+composer require phpmyadmin/shapefile
+``` 
+
+## History
+
+This library is based on BytesFall ShapeFiles library written by Ovidio <ovidio
+AT users.sourceforge.net>. The library has been embedded in phpMyAdmin for
+years and slowly developed there. At one point people started to use our
+version rather than the original library and that was the point we decided to
+make it separate package.
+
+[1]:https://getcomposer.org/
+