Remove unused code from the old controller
Remove use of default_vdata_of_typestring from xml file converter

This is a more stable approach.
Get rid of unused stuff in GRAPH_DATA

This was all leftover from the old way of dealing with node/edge data
Make sure we don't create wire-vertices when we wanted node-vertices

Previously, having something like
"node_vertices": ["a","b"]
in the graph JSON would create wire-vertices instead of the expected
node-vertices.