Reduce compilation time

[mofeing]

Storing index labels as parameters of NamedDimsArray structs is excessive for our use cases. The reason is that different parameters for NamedDimsArray implies different final structs and thus, compilation for each parameters case.

Although runtime performance is optimal, compilation time per simulation is overkilling.

Solution is to replace NamedDimsArray for some Tensor-like type where index labels are stored dynamically per instance and not per type.

[mofeing]

It have been solved by replacing NamedDimsArray with our own Tensor type.