all: make profiler.Init best effort
Created by: keegancsmith
This matches the pattern used by all our other instrumentation tools initializing. This also helps reduce verbosity in each of our main implementations.
I also made where we call profiler.Init more uniform. Now we always call it with the rest of the instrumentation setup.
Note: I used log15 here since I didn't want to introduce a dependency which assumed lib/log.Init had been called. Tackling logging in these sort of packages should be handled in another commit.
Test Plan: CI