Add support for NO_OVERWRITE config option

[Chaz6]

No description provided.

[amietn]

Thank you for contributing!

I believe this does not work if no_overwrite is set to False in the config file. It would still be interpreted as True.

One solution would be to call config.getboolean() instead of config.get() for options of boolean type.

[Chaz6]

Thank you for the feedback, I will amend the patch.