Allow the download directory to be different from the current working directory

[triple-j]

Allow the download directory to be different from the current working directory. This makes it easier to run this as a cron job in Linux.

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This PR also contains some clean ups to the --human-folders parameter.

Remove the need for the Game class to parse sys.argv. We'll store the option in the Library class and pass it to Game as needed.

Update the ArgumentParser.add_argument() call to make --human-folders a proper on/off flag.

Fix the naming convention for humanFolders. According to Python's PEP 8 Style Guide, function and variable names should be lowercase with words separated by underscores (aka snake_case). The rest of this project seems to follow PEP 8, so humanFolders should be human_folders.

[Emersont1]

could this be achieved more simply by changing the working dir with os.chdir()?

[triple-j]

could this be achieved more simply by changing the working dir with os.chdir()?

This has never crossed my mind.

The problem I could see with os.chdir() is that it can be unclear where a file is stored.

Say we use os.chdir() in itchiodl/downloader/__main__.py and leave Path(".") in itchiodl/game.py. If I was looking in itchiodl/game.py it wouldn't cross my mind that Path(".") wouldn't reference the directory where the program was run. Whereas if we use a variable (self.output_path) it is clear to the developer that the path can change.

In more complicated programs os.chdir() could cause more issues. If you need to save files in multiple folders, you'd need to make sure os.chdir() isn't run more than once. Otherwise where a file is saved could change based on where in the program you are.

I just think it is better to be explicit.