fixes bug where circle class d.node_type is not valid because node_types is not used in data. it now follows same procedure as applying the classes for the node, that is, checking the nodeTypes in the conf.
pulling in new change from upstream
updated sample data to reflect root node and node_type changes
removed all instances of node_type
Merge pull request #165 from ifjorissen/ifj_alchemy-bugs

misc bugs in alchemy.js