PHP Simple HTML DOM Parser v0.98 is released

1. Performance turning (boost 20%).
2. Supports "multiple calss" selector feature: <div class="a b c"></div>.
3. New "callback function" feature.
4. New "multiple selectors" feature: $dom->find('p,a,b');
5. New examples.
6. Supports extract contents from HTML features: $dom->plaintext;
7. Fix the bug of $dom->clear().
8. Fix the bug of text nodes' innertext.
9. Fix the bug of comment nodes' innertext.
10. Fix the bug of decendent selector with optional tags.
11. Change simple_html_dom_node method name from "text()" to "makeup()".