long data URI of font face in style tag cause browser freezing

[examan]

If style element contains long data URI, Autolinker will freeze at matcherRegex.exec.

@font-face { font-family: 'Work Sans'; src: local('Work Sans'), local('WorkSans-Regular'), url(data:font/woff;base64,............................................................); }

Style element should be skipped parsing to prevent this issue.

[examan]

#253

[gregjacobs]

Merged #253 - thanks!