This function will reactivate the task dispatcher after a call
to Forbid(). Note that calls to Forbid() nest, and for every
call to Forbid() you need a matching call to Permit().
INPUTS
None.
RESULT
Multitasking will be re-enabled.
NOTES
This function preserves all registers.
To prevent deadlocks calling Wait() in forbidden state breaks
the forbid - thus taskswitches may happen again.
EXAMPLE
No you really don't want to use this function.
BUGS
The only architecture that you can rely on the registers being
saved is on the Motorola mc68000 family.