[Hat] Hat-Gui, new tool

[Neil Mitchell]

> I wonder why w-hat doesn't use the standard Hat library. I see your point.
I believe Tom needs a lot more advanced access to the trace file than
any of the other tools, because he has much more powerful operations
for it.

> I suppose it would have been better if the standard Hat library used a
> kind of handle for the trace. So you would first need to get the handle,
> like for a file.
This is Tom's design of his library for Hat tracing, which he is going
to use in w-hat. It also allows things like comparing two trace
executions, by design.

Thanks

Neil