added cli args and help

[jperry004]

Description:
This pull request integrates argument parsing into the G-code processing script, making it more user-friendly and adaptable for automation. It adds support for a mandatory file path as a positional argument and an optional --skip-input flag for non-interactive environments.

Key Changes:
Positional Argument: Users must specify the G-code file path directly when executing the script.
Optional Flag: The --skip-input flag allows users to bypass manual input prompts.
Help Output: Enhanced help documentation is available to assist with new command-line options.

Behavior:
Running with Arguments: python prusa_slicer_post_processing_script.py /path/to/your/file.gcode
Skipping Input Prompts: python prusa_slicer_post_processing_script.py /path/to/your/file.gcode --skip-input
Accessing Help: python prusa_slicer_post_processing_script.py --help

No Arguments Provided: If the script is run without any arguments, it will display an error message and the usage information to help guide the user on how to properly execute the script.

[Wasupmacuz]

I've always felt that this was needed. Tested, working well. I've nitpicked a couple of details for optional changes but other than that, I think this will be helpful.

[Wasupmacuz]

This description is vague and maybe a little lazy. Maybe something like "Process overhangs within PrusaSlicer G-code files into circular arcs." would be clearer.

[Wasupmacuz]

Just nitpicking here: I think this would make more sense so import on line 29, after os.

[Wasupmacuz]

Tested in command line and PrusaSlicer. Working, approved.

[Wasupmacuz]

Failed to remember that I had to edit the getFileStreamAndPath method!
the new code:

def getFileStreamAndPath(path, read=True):
    try:
        if read:
            f = open(path, "r")
        else:
            f=open(path, "w")
        return f,path
    except IOError:
        input("File not found.Press enter.")
        sys.exit(1)

I tried running a branch of JP's code and could get it to work like mine. Comparing to my dev branch, I couldn't see any big differences. Couldn't figure it out until I compared my local code. Yikes!