Clean up README.

README.md

@@ -10,13 +10,6 @@ An object oriented, fully extensible CommonMark parser for PHP 5.4 and above.
 [**CommonMark spec**][commonmark-spec]
 
 * Forked from [Ciconia](https://github.com/kzykhys/ciconia) by [Kazuyuki Hayashi](https://github.com/kzykhys)
-* [Github Flavored Markdown](https://help.github.com/articles/github-flavored-markdown) support (disabled by default)
-	* Multiple underscores in words
-	* New lines
-	* Fenced code blocks
-	* Task lists
-	* Table
-	* URL Autolinking
 * Tested to comply with the [full CommonMark spec test suite][commonmark-spec]
 
 ## Requirements
@@ -36,7 +29,7 @@ Next, use Composer to install the library and its dependencies:
 
 ## Usage
 
-### Traditional Markdown
+### Parsing
 
 ```php
 use FluxBB\CommonMark\Parser;
@@ -47,107 +40,11 @@ $html = $parser->render('Markdown is **awesome**');
 // <p>Markdown is <em>awesome</em></p>
 ```
 
-### Options
-
-Option             | Type    | Default | Description                   |
--------------------|---------|---------|-------------------------------|
-**strict**         | boolean | false   | Throws exception if markdown contains syntax error |
-
-``` php
-use FluxBB\CommonMark\Parser;
-
-$parser = new Parser();
-$html = $parser->render(
-    'Markdown is **awesome**',
-    ['strict' => true]
-);
-```
-
 Rendering
 ---------
 
 The parser renders XHTML by default.
 
-## Extensions
-
-### How to Extend
-
-Creating extensions is easy, you only need to implement the `FluxBB\CommonMark\Extension\ExtensionInterface`.
-
-Your class must implement two methods.
-
-#### _void_ register(`FluxBB\CommonMark\Markdown` $markdown)
-
-Register any callbacks with the markdown event manager.
-`FluxBB\CommonMark\Markdown` is an instance of the `FluxBB\CommonMark\Event\EmitterInterface` (similar to Node's EventEmitter)
-
-#### _string_ getName()
-
-Returns the name of your extension.
-If your name is the same as one of the core extensions, the latter will be replaced by your extension.
-
-### Extension Example
-
-This sample extension turns any `@username` mentions into links.
-
-``` php
-<?php
-
-use FluxBB\CommonMark\Common\Text;
-use FluxBB\CommonMark\Extension\ExtensionInterface;
-
-class MentionExtension implements ExtensionInterface
-{
-
-    /**
-     * {@inheritdoc}
-     */
-    public function register(\FluxBB\CommonMark\Markdown $markdown)
-    {
-        $markdown->on('inline', [$this, 'processMentions']);
-    }
-
-    /**
-     * @param Text $text
-     */
-    public function processMentions(Text $text)
-    {
-        // Turn @username into [@username](http://example.com/user/username)
-        $text->replace('/(?:^|[^a-zA-Z0-9.])@([A-Za-z]+[A-Za-z0-9]+)/', function (Text $w, Text $username) {
-            return '[@' . $username . '](http://example.com/user/' . $username . ')';
-        });
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getName()
-    {
-        return 'mention';
-    }
-}
-```
-
-Register your extension.
-
-``` php
-<?php
-
-require __DIR__ . '/vendor/autoload.php';
-
-$parser = new \FluxBB\CommonMark\Parser();
-$parser->addExtension(new MentionExtension());
-echo $parser->render('@admin my email address is [email protected]!');
-```
-
-Output
-
-``` html
-<p><a href="http://example.com/user/admin">@admin</a> my email address is [email protected]!</p>
-```
-
-Each extension handles string as a `Text` object. See [API section of kzykhys/Text][textapi].
-
 ## Command Line Interface
 
 ### Usage