C++ style memory allocation.

[TeachRaccooon]

At the moment, I use calloc all throughout the repo.
Makes sense to change that.
Riley's comment:

If you do new T[length_of_buffer]{} (not the curly braces), then it will zero-initialize.
An advantage to new is that it will work if T is std::complex or std::complex (defacto-standard datatypes for complex floats in C++). I don't know if calloc will work in that situation.
That said, calloc apparently works with realloc, while new does not.
I says we open a GitHub issue about this so we establish a policy for new contributions.

We also need to consider getting rid of the internal allocations.
The discussion on all that is present in PR#71