Update docs badge in README

Update the URL of the docs badge to include it from inch-ci.org instead of inch-pages.github.io (the former being the successor of the Inch Pages project).

[ci skip]

README.md

 Paperclip
 Paperclip
 =========
 =========
 
 
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+[![Build Status](https://secure.travis-ci.org/thoughtbot/paperclip.png?branch=master)](http://travis-ci.org/thoughtbot/paperclip) [![Dependency Status](https://gemnasium.com/thoughtbot/paperclip.png?travis)](https://gemnasium.com/thoughtbot/paperclip) [![Code Climate](https://codeclimate.com/github/thoughtbot/paperclip.png)](https://codeclimate.com/github/thoughtbot/paperclip) [![Inline docs](http://inch-ci.org/github/thoughtbot/paperclip.png)](http://inch-ci.org/github/thoughtbot/paperclip)
 
 
 Paperclip is intended as an easy file attachment library for Active Record. The
 Paperclip is intended as an easy file attachment library for Active Record. The
 intent behind it was to keep setup as easy as possible and to treat files as
 intent behind it was to keep setup as easy as possible and to treat files as