Basic properties display (incl. provenance) for nodes and edges.

NOTE that this bumps the argus domSource from 'ottol' to the
synthetic tree, disabling the Extract Subtree feature.
Added a temporary hack to inject ottol id (and domSource) into treeData.

This lets us demo the Extract Subtree feature, at least for URLs that
specify an ottol id, eg:

http://localhost:8000/opentree/argus/ottol@805080/life

Hopefully we can include 'domSource' and 'sourceID' attributes for all
nodes in the view-tree JSON.