traceBatch Verbosity problem

[Stephen Weeks]

> The "bug" is that the application of tracerTop is occuring in the
> definition of the structure, so it's seeing the default Verbosity setting
> of Silent before the command line args set it to another value.
> 
> I'm not quite sure what is the right thing to do.  I can obviously fix it
> by pushing the Verbosity.<= test into either the message printer or the
> function application, but that seems a shame, because we'll either pay for
> computing the total time (and not print it) or pay for a verbosity test at
> every function application.  I guess the latter isn't so bad, but it is
> what I was hoping to avoid.

Another possibility would be to move the tracers inside the functions, so that
there is a verbosity test once per compile (or chunk, or something better than
per function call).  Although you should probably measure the time to see if it
matters.