Genie:  Use global timer for yielding to host OS

This fixes the issue on OS X where incoming network requests are blocked
until an event (e.g. key down) is received by MacRelix.  It also affects
the stale psmon display, addressing the most common symptom of two psmon
entries (one vforking, one running and about to exec) showing long after
the processes have finished creating the applet and exited.  But similar
artifacts persist, however.
Genie:  Remove unused per-process resume timestamp