Calling functions from threads may be broken

[Bravotic]

Seems to work for some functions like puts, however not others like putchar. Halting progress on threads until this is solved.

[Bravotic]

The problem happens to be a problem with how borrows are implemented, and is now fixed. However, now the reading syscall appears to be broken. So further work is being done.

[Bravotic]

Threading is removed from high priority.