Merging DataType, Backend, ForwardDims into Compile()

Handling DataType, Backend and Tensor's dimensions and format is messy. Each caracterisitc may depend on another.

• Cannot run ForwardDims if necessary Transpose Operators have not been set
• Cannot run ForwardDims if uncompatible data formats
• Cannot handle format if backend is not known
• ...

Solution

Rather than leaving the user run each of these functions in an undefined order, it would be best to have a single function to do them in the right order without thinking further. Its goal would be to "set the GraphView ready for execution".

Here is how it would work:

1. Transform the GraphView to manage Backend:
   • insert Transmittors Operators between two Nodes not running on the same backend
2. Transform the GraphView to manage DataType:
   • insert Transpose Operators between two Nodes not using the same format
   • insert TypeConversion Operators between two Nodes not using the same DataType
3. Deduce dimensions