Allow asterisk css queries

[LeoSchleicher]

Hi, In one of my stylesheets are there an asterisk css rules:

''' * {color:#fff;} '''

This small change allows them, I don't know if there is a really useful improvement, so I make no pull request for now.

https://github.com/LeoSchleicher/CSSParser/commit/9cb13710aa89a4e039ba5c30d51df5a004206c1a