Changed the text representation for DOMNodes to 'DOM<Element>Node', where the first letter of <Element> will be uppercased and the rest remains intact as it was
Added toString method override, fixed issue with incorrect node type, added tests for CDATASections

lib/dom/cdatasection.js
+ added toString method override to return '[object DOMCDATASection]'

lib/dom/document.js
* fixed issue with document.createCDATASection, which used type 3 (DOMText) instead of 4 (CDATASection)

test/cdata.js
+ added various tests, similar to comment (+1 squashed commit)
Squashed commits:
[10cdcad] Core.toString now properly removes all non-word characters, not just the first
Fixed issue where appendChild and insertbefore on the document itself would fail
Added processing-instruction module and tests (+3 squashed commits)
Squashed commits:
[4c8cc50] Added XMLSerializer module, which accepts DOMNodes and returns the XML representation
[57a266e] removed debug statements
[945f554] Added ProcessingInstructions to the Simple factory
Merge branch 'lab_test'