Returning from filter if matches are empty.
Moved around alias line.
Wrapped element to search in NodeSet. Changed selectors to selector.
Cleaned up some unneaded bits in SubstitutionContext.
Reworked the wrapping root in NodeSet implementation in css_select.
Updated documentation to state more things about css selectors with substitution values.
Removed mention of css_select supporting substitution values. It is not tested anywhere.