* Remove Subsystems map and replace with RegisterSubSystem
* Clean up the logger
* Fix LOGFLAGS and make LongFile work correctly
* Parallelize the logger backend
* More logger cleanup
* Initialize and close the logger backend wherever it's needed
* Move the location where the backend is closed, also print the log if it panics while writing
* Add TestMain to reachability manager tests to preserve the same log level
* Fix review comments
Co-authored-by: Svarog <feanorr@gmail.com>
* [NOD-1223] Move all network stuff into a new network package.
* [NOD-1223] Delete the unused package testutil.
* [NOD-1223] Move infrastructure stuff into a new instrastructure package.
* [NOD-1223] Move domain stuff into a new domain package.
