code: public String getPreference(String prefKey, String defaultValue) {
          return props.getProperty(prefKey, defaultValue);
      }
docs: Returns the value of the specified preference.
  
  @param prefKey      The preference to look for
  @param defaultValue The value to be returned if the key was not found in the properties file
  @return The value of the specified preference or the {@code defaultValue} if the key was not found