[FIX](protovis mouse) was still sensitive to the padding of the canvas div.
[DOC][FIX](extension points) Some charts' extension point classes did not have the base class specified, causing some ext. points to be missing
[DOC][FIX](default value tooltipOffset) Removed the default, cause it really is dynamic.
[DOC][IMP](categories) Improved category-grouping of properties by adapting some category names and using smarter rules in the XSL