Storing the size of the blocks is now only activated when DEBUG__MEMFILL
has been defined.

We replace instances of void* w/ char* arithmetics.

This allows system_allocator.c to be compiled with MSVC.

Also we introduce a struct to represent the size_t header.

Refactored all of the desugaring code to no longer depend on memory being initialized to 0. Everything is about 12% faster now.