Configure the logging at compile time
Instead of guessing it from test/release build, allow a compilation flag to influence how much is logged. Default to debug logging, as trace is really annoying most of the time.
Also, switch to running tests in debug mode, as we no longer need to limit the output by release build.
This is related to #9 (closed), but there's much more to be done there.
Also, don't fear this MR, there's not much code and none of it is fancy C++