Fix mistaken use of the PlottingFunctionFactory parent class ___init__ function
This came from Mike Walters. I've been seeing the behavior in the newer version of Glance too, but hadn't looked into it yet. Mike said:
I keep getting error messages like this:
2020-08-11 22:56:51 ERROR: (plotcreatefns) Someone has instantiated PlottingFunctionFactory. This class is NOT meant to be instantiated.
The problem here is that the subclasses of the PlottingFunctionFactory class don't have their own init() methods, so they inherit the init() method of PlottingFunctionFactory, which logs the error message. In spite of the error message, Glance runs normally. So this isn't a show stopper - it's just annoying.