Loads Thucydides preferences from a local file called thucydides.properties.
Thucydides options can be loaded from the thucydides.properties file in the home directory, in the working directory,
or on the classpath. There can be multiple thucydides.properties files, in which case values from the file in the
working directory override values on the classpath, and values in the home directory override values in the working
directory. Values can always be overridden on the command line.