extGEX: Clean up

Removes old code from FormReversiones and FormExpropiationsLauncher
extGEX, extAudasaCommons: extracts anonymous class to its own type

Creates a NonEditableDefaultTable model class
extGEX: Displays 'Importe (Ptas)', 'Importe (€)' in form 'reversiones'
extGEX: Computes 'importe ptas' in 'añadir reversión'