Selector tests

Moving away from using the sizzle tests as our selector compliance is to the w3c and not jquery.

Basically, I've cached http://javascript.nwbox.com/NWMatcher/release/test/css3-compat/css3-compat.html locally and parse the css out on the fly, apply it manually and ensure that all of the selections are actually valid.

It may be worth looking into using http://www.w3.org/Style/CSS/Test/CSS3/Selectors/current/xhtml/full/flat/index.html instead, but converting them into jsdom tests will require far more effort.

```
 level1/core                        532/532      100%     
 level1/html                        238/238      100%     
 level1/svg                         527/527      100%     
 level2/core                        283/283      100%     
 level2/html                        697/697      100%     
 level2/style                         11/11      100%     
 level2/extra                           4/4      100%     
 level2/events                        24/24      100%     
 level3/xpath                         93/93      100%     
 window/index                           5/5      100%     
 window/script                        10/10      100%     
 window/frame                         14/14      100%     
 selectors/index                        1/1      100%     
 jsdom/index                          86/86      100%     
 jsonp/jsonp                            1/1      100%     
 browser/contextifyReplacement          4/4      100%     
 browser/index                        22/22      100%     
------------------------------------------------------
TOTALS: 0/2552 failed; 100% success
TIME: 42903ms
```