Merge pull request #1662 from UziTech/docs-tokenizer-option

add tokenizer to option docs

docs/USING_ADVANCED.md

@@ -57,6 +57,7 @@ console.log(marked(markdownString));
 |silent      |`boolean` |`false`  |v0.2.7   |If true, the parser does not throw any exception.|
 |smartLists  |`boolean` |`false`  |v0.2.8   |If true, use smarter list behavior than those found in `markdown.pl`.|
 |smartypants |`boolean` |`false`  |v0.2.9   |If true, use "smart" typographic punctuation for things like quotes and dashes.|
+|tokenizer    |`object`  |`new Tokenizer()`|v1.0.0|An object containing functions to create tokens from markdown. See [extensibility](/#/USING_PRO.md) for more details.|
 |xhtml       |`boolean` |`false`  |v0.3.2   |If true, emit self-closing HTML tags for void elements (<br/>, <img/>, etc.) with a "/" as required by XHTML.|
 
 <h2 id="highlight">Asynchronous highlighting</h2>