feat: allow admin to set logging format from config.ini This is prep work for adding a per thread logging variable that can be used to tie all logs for a single request together. This uses the same default logging format as before, just moves it to config.ini. Also because of configparser, the logging format has to have doubled % signs. So use: %%(asctime)s not '%(asctime)s' as configparser tries to interpolate that string and asctime is not defined in the configparser's scope. Using %%(asctime)s is not interpolated by configparser and is passed into Roundup.

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