:not(), [att=val], [att!=val], [att|=val], [att*=val], [att~=val],
[att^=val], [att$=val]
Note that the selection is now returned as a simple Set, breaking the
abilty brought in by #8 and #9 tot :select() or () on the selection. Of
course, the elements in the returned Set are still ElementNodes that
can be selected upon.
... regarding [attribute=value] and other matching.
Also explained (in comments) the different matching patterns.
And fixed a bug where /> would be listed as an attribute.
And added a few more tests.
Extracting microdata is fairly tedious compared to microformats, due to
its generality. Should probably be included as a standard function of
the parser, or even better, as a separate module, which then can
concern itself with being fully standards compliant.