minifier crashes on attribute names that end with $ #377
Description
The following document can't be minified, it crashes with "Error: Minification error":
<html>
<body class$="foo">
</body>
</html>
$ html-minifier out.html
Error: Minification error
This stops html-minifier from being used on Polymer 1.0:
https://www.polymer-project.org/1.0/docs/devguide/data-binding.html#attribute-binding
$ is a valid character in an attribute name:
https://html.spec.whatwg.org/multipage/syntax.html#attributes-2