... handling any interrupt service routines.
This was causing crashes while running /userspace/ apps without any
syscalls being triggered, presumably due to switching at awkward times.
- Free process resources when a process exits (reaped in next process
cycle; should probably reap after a wait() or something)
- Free process struct after wait()
- Fix page allocation
- Fix fork() return value for child process (attempted to write to an
invalid point in kernel-stack memory)
We shouldn't be triple faulting randomly anymore!
Continue investigating the fork() return value, as there was a bugged
return at some point during executon of a test run of thrash-process.
