Allow logging timings to a logger

Would there be any reason not to allow an option to have the timeit decorator be able to log the information to a logger instead of sys.stderr?

Start by locating the timeit decorator and the code that writes timing information to sys.stderr. Check the existing tests around this decorator, then define completion as supporting an optional logger while preserving the current stderr behavior and covering the new option with tests.

Written by the indexing model from the issue text.