Add functionality to get memory regions and permissions.

[Andoryuuta]

A way of getting all memory regions within a process along with the region permissions (read, write, execute) needs to be added all of the platform back-ends. This needs to be added before a search functionality can be added.

Windows via VirtualQueryEx.

Linux via /proc/pid/maps

OSX via vm_region which is part of mach's virtual memory interface