Add a trampoline to Node.add_child in order to set None default value to avoid conversion of nullptr -> std::shared_ptr.

Fix numpy -> tensor with latest tensorImpl changes (copyFromHost instead of setRawPtr) + Use of std::int32_t instead of in and std::int64_t instead of long to fit Data.hpp convention.

- 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

[Fix] set FC/ConvDepthWise parameter sizes at construction by adding the number of input channels in construction parameters