Profiling module precompilation

Would be nice to be able to get a printout that shows how much the “self time” and total time of loading a package (+ deps) is.

So if you do using MegaMLFramework it would show something like:

name                 self   total
MegaMLFramework      2 s    20 s
Flux                 6 s    18 s
Zygote               12 s   12 s