[DGD] DGD MP and a TLS idea

[Steve Wooster]

     It occurred to me that what I meant by my description of call_outs 
being "effectively single-threaded" might not have been clear... From what 
I can tell, only one call_out can occur at a time. You can't have two 
different call_outs running on two different processors, since they'll 
always conflict with each other when checking if they've been suspended. 
(or is this not true, since they don't necessarily write to variables?)

-Steve Wooster