Update Readme.md (#125)

* Update Readme.md

* Update README.md

Co-Authored-By: Robert Jackson <me@rwjblue.com>

README.md

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 Ember-load-initializers [![Build Status](https://travis-ci.org/ember-cli/ember-load-initializers.svg?branch=master)](https://travis-ci.org/ember-cli/ember-load-initializers)
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-A tiny add-on to autoload your initializer files in ember-cli.
+A tiny add-on to autoload your initializer and instance initializer files in ember-cli. This add-on iterates over files inside `app/initializers` and `app/instance-initializers` and invokes the `app.initializer` and `app.instanceInitializer` methods respectively, by passing on the resolved name of the files.
 
 Installation
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