This adds some structures necessary to support multiple memory regions
in the future. It also adds support for different system memory types
and the new linear heap mapping at 0x30000000.
This enables more dynamic management of the process address space,
compared to just directly configuring the page table for major areas.
This will serve as the foundation upon which the rest of the Kernel
memory management functions will be built.
memory.cpp/h contains definitions related to acessing memory and
configuring the address space
mem_map.cpp/h contains higher-level definitions related to configuring
the address space accoording to the kernel and allocating memory.
