- Remove setInput in Node
- Change setDatatype to setDataType in GraphView and Tensor binding
- Add namespace comment
- Update Node includes
- Run forwardDims() only if operators use Tensors

- Add a common parent class to each Operator using Tensors: OperatorTensor
- Gather shared operator functions in OperatorTensor
- Add generic mInputs and mOutputs attributes for OperatorTensor
- Add an enum to identify the type of Data used by each Operator
- Change Inputs, DataInputs, Outputs for Inputs, Data, Attr, Outputs for less confusion

Changed outputs() and getNbDataInputs() in GraphView to achieve consistent behavior (clarified in doctring)