- [Add] Attributes: __str__(), __repr__() and dict() methods
- [Add] GraphView: __repr__(), __len__() methods
- [Add] Node: __repr__() method
- [Add] Operator: __repr__() method and attr property
- improve Tensor __str__ method if it is empty
- change DataType to lower case for python

- add Tensor operators +,-,*,/
- add __repr__ funciton to Tensor
- add operator constructor to each python binding
- fix identity_op Base class declaration in binding

- add Tensor operators +,-,*,/
- add __repr__ funciton to Tensor
- add operator constructor to each python binding
- fix identity_op Base class declaration in binding

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