Update README

Author: geowarin

README.md

@@ -2,8 +2,97 @@
 
 [![Build Status](https://travis-ci.org/geowarin/friendly-errors-webpack-plugin.svg?branch=master)](https://travis-ci.org/geowarin/friendly-errors-webpack-plugin)
 
-Not ready yet. See [this](https://github.com/facebookincubator/create-react-app/issues/401)
-and [this](https://github.com/geowarin/tarec/pull/16) for more context.
+Friendly-errors-webpack-plugin recognizes certain classes of webpack
+errors and cleans, aggregates and prioritizes them to provide a better
+Developer Experience.
+
+It is easy to add types of errors so if you would like to see more
+errors get handled, please open a [PR](https://help.github.com/articles/creating-a-pull-request/)!
+
+## Demo
+
+### Build success
+
+![success](http://i.imgur.com/MkUEhYz.gif)
+
+### eslint-loader errors
+
+![lint](http://i.imgur.com/xYRkldr.gif)
+
+### babel-loader syntax errors
+
+![babel](http://i.imgur.com/W59z8WF.gif)
+
+### Module not found
+
+![babel](http://i.imgur.com/OivW4As.gif)
+
+## Options
+
+You can pass options to the plugin:
+
+```js
+new FriendlyErrorsPlugin({
+  compilationSuccessInfo: {
+    messages: ['You application is running here http://localhost:3000'],
+    notes: ['Some additionnal notes to be displayed unpon successful compilation']
+  },
+  onErrors: function (severity, errors) {
+    // You can listen to errors transformed and prioritized by the plugin
+    // sevrity can be 'error' or 'warning'
+  },
+  // should the console be cleared between each compilation?
+  // default is true
+  shouldClearConsole: true,
+  
+  // add formatters and transformers (see below)
+  additionalFormatters: [],
+  additionalTransformers: []
+})
+```
+
+## Adding desktop notifications
+
+The plugin has no native support for desktop notifications but it is easy
+to add them thanks to [node-notifier](https://www.npmjs.com/package/node-notifier) for instance.
+
+```js
+var NotifierPlugin = require('friendly-errors-webpack-plugin');
+var notifier = require('node-notifier');
+var ICON = path.join(__dirname, 'icon.png');
+
+new NotifierPlugin({
+    onErrors: (severity, errors) => {
+      if (severity !== 'error') {
+        return;
+      }
+      const error = errors[0];
+      notifier.notify({
+        title: context.pkg.name,
+        message: severity + ': ' + error.name,
+        subtitle: error.file || '',
+        icon: ICON
+      });
+    }
+  })
+]
+```
+
+## API
+
+### Transformers and formatters
+
+Webpack's errors processing, is done in four phases:
+ 
+1. Extract relevant info from webpack errors. This is done by the plugin [here](https://github.com/geowarin/friendly-errors-webpack-plugin/blob/master/src/core/extractWebpackError.js)
+2. Apply transformers to all errors to identify and annotate well know errors and give them a priority
+3. Get only top priority error or top priority warnings if no errors are thrown
+4. Apply formatters to all annotated errors
+
+You can add transformers and formatters. Please see [transformErrors](https://github.com/geowarin/friendly-errors-webpack-plugin/blob/master/src/core/transformErrors.js),
+and [formatErrors](https://github.com/geowarin/friendly-errors-webpack-plugin/blob/master/src/core/formatErrors.js)
+in the source code and take a look a the [default transformers](https://github.com/geowarin/friendly-errors-webpack-plugin/tree/master/src/transformers)
+and the [default formatters](https://github.com/geowarin/friendly-errors-webpack-plugin/tree/master/src/formatters).
 
 ## TODO