improve documentation in readme

Author: jelhan

README.md

@@ -1,7 +1,7 @@
 # ember-cli-browser-navigation-button-test-helper
-[![Build Status](https://travis-ci.org/jelhan/ember-cli-browser-navigation-button-test-helpers.svg?branch=master)](https://travis-ci.org/jelhan/ember-cli-browser-navigation-button-test-helpers)
 
-Test helper to simulate browsers back and forward buttons in acceptance tests.
+Test helper to simulate browser's back and forward buttons in acceptance tests
+of Ember applications.
 
 Compatibility
 ------------------------------------------------------------------------------
@@ -20,14 +20,20 @@ ember install ember-cli-browser-navigation-button-test-helper
 Usage
 ------------------------------------------------------------------------------
 
-This addon exportes three test helpers: `setupBrowserNavigationButtons()`, `backButton()` and `forwardButton()` from `ember-cli-browser-navigation-button-test-helper/test-support`. `setupBrowserNavigationButtons` should be called at the very beginning of every acceptance test which should use the later ones. It registers a service to manage history. The other two simulates clicks on browsers back and forward buttons.
+This addon exports three test helpers from `ember-cli-browser-navigation-button-test-helper/test-support`:
 
-There is an usage example [in this acceptance test](https://github.com/jelhan/ember-cli-browser-navigation-button-test-helpers/blob/master/tests/acceptance/browser-navigation-buttons-test.js).
+- `setupBrowserNavigationButtons`,
+- `backButton` and
+- `forwardButton`.
 
-Known limitations
-------------------------------------------------------------------------------
+`setupBrowserNavigationButtons` must be called in every acceptance test which
+uses `backButton` and `forwardButton` _before_ `visit()`. It registers a service
+to track and manage the history.
+
+`backbutton` and `forwardButton` simulates the browser's back and forward
+buttons by firing a transition using `RouterService.transitionTo()`.
 
-Support for old-style acceptance tests (before RFC #232 and #268) was dropped in `v0.1.0`. You could use `v0.0.5` if you need to support them, but this one does not support Ember 3.x.
+Please find an usage example [in this acceptance test](https://github.com/jelhan/ember-cli-browser-navigation-button-test-helpers/blob/master/tests/acceptance/browser-navigation-buttons-test.js).
 
 
 Contributing