Started on regulaization in Loss.h. I need to refactor the matsum.h since I need a total sum over the matrix. Also matmul needs a elementwise matmul function, which is the next this in the ragulaization
I've implemented alot of support functions that needs to be refactored, optimised and tested; mean.h, exponential.h, matdiv.h matsum.h matsubtract.h. Maybe we need to have a look at if matdiv/matmul should be in the same. Same with matadd/matsubtract and if some of it should be in matvec.h.