Added badge for «Inline docs» service (https://inch-ci.org/)

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README.md

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 [![Test Coverage](https://codeclimate.com/github/activescaffold/active_scaffold/badges/coverage.svg)](https://codeclimate.com/github/activescaffold/active_scaffold)
 [![Dependency Status](https://gemnasium.com/activescaffold/active_scaffold.svg)](https://gemnasium.com/activescaffold/active_scaffold)
 [![Gem Version](https://badge.fury.io/rb/active_scaffold.svg)](https://badge.fury.io/rb/active_scaffold)
+[![Inline docs](https://inch-ci.org/github/activescaffold/active_scaffold.svg?branch=master)](https://inch-ci.org/github/activescaffold/active_scaffold)
 
 ActiveScaffold provides a quick and powerful user interfaces for CRUD (create, read, update, delete) operations for Rails applications. It offers additonal features including searching, pagination & layout control.  Rails 3.2 and 4.x are supported, ruby >= 1.9 required. For rails 4 is recommended >= 4.0.5.