Add Memory Management and Scheduler Management Primitives

These patches add three new pieces of functionality:
 * Support a process managing its scheduler CPU core/set affinity so a process can pin itself to a particular NUMA node
 * Provide Rust-ier wrappers for mmap and relatives for those of us who do sundry things with...
 * shm_open/shm_unlink for shared memory segment management in shmfs.