Restrict reported traces to a given module

[cossio]

It would be nice if the output flamegraph could be restricted to showing only lines coming from a module. When I am benchmarking my code, I usually don't care about the calls to Julia base or stdlibs, for example.

[timholy]

There's a variant of this now: you can color the calls from different modules differently, see https://github.com/timholy/FlameGraphs.jl