Allocator Improvements

[JoltedJon]

@VictorSohier some requested improvements to Allocators

• Documentation on allocators, how to use them, examples, generally when you would opt to use each type of allocator etc.
• Since it is unlikely that Slice would be used without an allocator and allocator requires slice it is likely that Slice doesn't need to be it's own module and can be put into allocator.cppm
• It might be wise to mark some functions with [[nodiscard]]

[JoltedJon]

Guys we need to urgently not fix this

[mcdubhghlas]

github sucks, pls ignore.