Begin refactoring. First move Output and its subclasses into outputs.py...
...then fix up the code we moved. Then, fix up str-vs-bytes bugs caused by the move to Python 3 and not handled by the 2to3 utility. Now things seem to be working again.
gitignore change
Refactor outputs.py for more idiomatic code
Begin refactoring by moving Updater and subclasses into updaters.py...
...and make the refactored code work by adding the right imports
Both updaters had been broken by the move to Python 3 as well. Fixed.
Fix usage of tarfile's extractfile() library function. It can return None if the requested file within the archive is not a regular file or symlink to one.