Allow tracer to skip arguments

[byte-sculptor]

Right now: OptimizerEvaluationReport.add_pickled_optimizer includes the string of bytes for the pickled optimizer in the trace.

We should add an argument to the trace() decorator to exclude parameters from logging.

[amueller]

Semi-related, how does the Tracer compare with standard python profiling traces? I haven't really understood what the additional benefit of using the tracer is so far.

[byte-sculptor]

Which of the standard tools do you have in mind?

[amueller]

python profiling together with snakeviz and line profiler. Though neither gives detailed runtime histograms as the current setup does.