Extract Node initialization functions into a kernel file

[Benny-Nottonson]

Is your feature request related to a problem? Please describe.
Tensors / Nodes are currently initialized for weights and biases using code that is held within Tensor and Node, rather than making a unary operation to do so, this should be changed.

Describe the solution you'd like
The initialization kernels should be held within a seperate kernel file or added to an existing one, and they should use vectorized SIMD operations.

Describe alternatives you've considered
The current implementation works but is significantly slower than other related functions and makes the structure of the code confusing.