* kick off new os procs (machs) as needed
* add sys·sleep for testing
* add Lock, Rendez
* properly lock mal, sys·newproc, scheduler
* linux syscall arg #4 is in R10, not CX
* chans are not multithread-safe yet
* multithreading disabled by default;
set $gomaxprocs=2 (or 1000) to turn it on
This should build on OS X but may not.
Rob and I will fix soon after submitting.
TBR=r
OCL=13784
CL=13842
