deep copy each Statement before adding it to the Graph.  this is so that Statement.getModel() works as expected.
improve and document triple chooser popup. remove incorrect error reporting from Graph.  give Edge a singlet Statement getter.
improve user feedback for gitty
add dev notes on selection modifiers.
Merge branch 'dev' of https://github.com/kdbanman/nodes into dev
format readme.
fixed Edge rendered string
discover bug and maintain TODO