The compat.SYSTEM is now set to 'Windows' when 'Microsoft' is detected.

This is for easier identification of MS Windows systems, as either string could be used.
Created the new gui.text module for holding all of the unicode text for the GUI.

This module contains unicode strings for the various analysis types, which are then all defined in
one location.  This is for consistency.
Converted the model-free user function definitions to use the new gui.text module strings.
Shifted the gui.text module to lib.text.gui to avoid a fatal circular import in the GUI.