CMS-2054 Rename classes in app_wizard_form_input to be postfixed with View
Added "abstract" method getValue on BaseInputTypeView for correctly getting value from any kind of input occurrence. Method is overridden in each input type.
Added support for:
 - creating minimum number of "value occurrences" for an input type
 - each occurrence can be removed by a button (if not minimum or last one is reached)
 - new occurrences can be added (but maximum is not obeyed yet)