* Add onPaint callback to NodeDataModel for custom painting stuff
* Add NodePainterDelegate that allows for custom painting
* Fix state call
* Update NodePainter.cpp
* Automatic type cast node insertation working in a basic manner
* Port paint fix to handle convertible types
* Code cleanup, documentation,, and minor fixes
* Fixing master merge
* Master merge fix 2
* Master merge fix 3
* Code style fixes
* Fixing logic error, where typecast node with the same input-output types were permitted
* Fixes based on @russelltg 's suggestions
* Got rid of unique_ptr static_casts
* Partial fixes from the code review
* Merging master into branch vol. 3
* Node validation and error display implemented
* Added option to iterate through nodes in the scene. (Useful to read out data from all the nodes, makes code generation based on the graphs easier.)
* Visual error fix for nodes that change size depending on input, plus minor styling and logic fixes in the example, based on the comments of @russelltg
* Validation extended to handle warnings, based on the idea of @russeltg ; Error display colors now come from the style system; Additional bugfixes
* DefaultStyle.json identation fix
* FlowScene.cpp identation fix
* Travis build test fix
* Add option to set custom captions for node ports
* Calculator example modified to consistently use custom ports labels where it makes sense
* Minor fixes in modified code
Dmitry Pinaev
Davide Faconti
Remigiusz Kołłątaj
Russell Greene
David Bachrati
Jean-Michaël Celerier