Variable standardization and documentation

[TaylorOshan]

Opening this issue to further discuss whether or not we should include an option that automatically standardizes variables and if we do then how we can document that it has been done to ensure the user does not misinterpret their results. Thought we have discussed having a standardization option, it might be useful to leave this out of the API. Standardization is quite simple to do yourself, and I would assume that if you can access and utilize the command-line API for MGWR than you can also sort out your own standardization. Then it follows that if you are self-standardizing the variables than you know that it is being done and interpretation is left up to the user as usual. Also, we can have an automatic standardization option in the GUI (even if it is not part the GUI). Since the GUI has an output statement and educational materials we can update those to include notes that remind the user their variables are standardized and how to interpret their results.

[Ziqi-Li]

I agree. How about that, for the GUI part, we will have a checkbox for standardization, and it can be checked by default if user chooses to run MGWR. Also this will be shown in the summary output.

[weikang9009]

Makes good sense. I still think that it might be helpful to include the standardization option though we assume that it is simple and straightforward for the API users to make the standardization happen. The default could be using the original variables. In the docstring of this standardization parameter, we can clarify the difference in interpreting optimal bandwidths by setting this parameter as True or False.