TaskManager progress

[Patricia Shanahan]

I did the first tests of my new TaskManager today. I can't benchmark 
very accurately because of a QA test running on the same computer, but 
it seems to be about the same without dependencies, and significantly 
faster with dependencies. Specifically, it removes the single task 
bottleneck.

I'll next do more testing, benchmarking, and tuning in my own environment.
Patricia