Call get_setting with setting.name

[gamboz]

Sometimes the function utils.settings_handler.get_setting() is called with a wrong argument.

The function expects a string as second argument (setting_name), but here and there it is called with a core.Setting object instead. I think that everything works fine anyway because str(Setting) is Setting.name, but I thought I should mention :slightly_smiling_face:

Here I fix a couple of calls, and I add (temporary) code to report if someone is calling with non-str argument.