Change name of modules/name and possibly refactor?

Created by: juga0

This is not something important, nor should change the functionality, but before the code grows in complexity and size, maybe it's worth to take into account. __main__.py could be called sbws.py or cli.py. The main functionality of the subcommands is inside the module commands, which maybe should be call core and/or split the args parsing to other files. What do you think?