Taxonomy Hypergraph

I hacked together a solution to Hypergraph for taxonomy. Replace the file graphs/hg.php with the attached hg_tax.php. I basically changed the function hypergraph_get_menu. There are some caveats:

1) Still only able to render one graph unless I am missing something.
2) This code hardcodes to the Vocabulary with $vid=1. If you have multiple vocabularies, you'll have to adjust the code. Also, have to adjust ref links since 1, in: <ref xlink:href="taxonomy/term/1,' . $list->tid . '" /> refers to vocabulary $vid=1.
3) Vocabulary is given name "tags" and depth = 0, all terms and nodes have depths > 0.
4) The code sets one node depth for each node ID. Therefore, if you have a node with multiple tags, it will choose the depth based on first term in vocabulary that the code utilizes.