XML namespaces about phpquery HOT 5 OPEN

Ive briefly examined namespaces issue and it can be tricky to implement. At this
moment ive scheduled it for Milestone-Release2.0.

I will look at it closer and do some tests when dealing with issue #23 - XML
compatibility:
http://code.google.com/p/phpquery/issues/detail?id=23
Then it sould be more clear, and i will update this issue.

Sources im basing on:
 * http://www.w3.org/TR/xml-names/
 * http://www.w3.org/TR/css3-namespace/
 * http://php.net/manual/en/domxpath.registernamespace.php
 * http://people.ischool.berkeley.edu/~felix/xml/php-and-xmlns.html (outdated ?)

First implementation efforts available in r295. Please test and post feedback.

Some test OK for me.
But I don't really use it.

Query namespace|* selects all elements not those from specified namespace.

Query namespace|* selects all elements not those from specified namespace.