Support for "matches-any" pseudo-class :matches()

[redapple]

CSS Selectors Level 4 (draft) proposes the :matches() pseudo-class (apparently inspired by :any() already supported in some browsers)

Example from https://www.sitepoint.com/css-selectors-level-4-the-path-to-css4/

div:matches(.active, .visible, #main)

There can be a need for or relations on XPath predicates and :matches() could allow that.

[wRAR]

Note that https://drafts.csswg.org/selectors-4/#matches now says that the pseudo-class should be :is(), while :matches() can be supported as an obsolete alias.

[wRAR]

Fixed in #109