* Checkpoint.
* Add doco to graph.h and graph_base.h.
Change NodeConstIterator to return a reference to clearly advertise no nullptr's are going to be returned as it's only iterating valid Nodes.
Fix some code analysis warnings.
* Make a couple of APIs return a reference instead of a pointer as they never return nullptr.
* More doco and some minor naming cleanups.
* Cleanups
Couple more consistency changes.
* Fix CUDA test file
* Fix invalid line.