Fix for parse error in files.handlebars

Heya,

I get following error when compiling the docs.

The attached change fixes an issue for me.

````
$ grunt yui-doc-compile
Running "yuidoc:compile" (yuidoc) task
Start YUIDoc compile...
Scanning: src/widgets
Output: dist/demos/api
Fatal error: Parse error on line 2:
...    <h1>{{{fileName}} <small>File</smal
----------------------^
Expecting 'CLOSE_UNESCAPED', got 'CLOSE'
````

````
$ node -v
v0.10.25
$ npm -v
1.3.24
````