[Patch] Bugfix for cursor in non-public fields

[Leon Winter]

Hi Thomas,

having a field in !O_PUBLIC state currently results in undesired results:
When entering data, the displayed cursor is advanced outside of the field
boundary because the scrolling calculation is not executed in
_nc_Refresh_Current_Field but the cursor is nontheless set in
_nc_Position_Form_Cursor.

There are two different ways to go about this:
(1) The input mechanism should be behave exactly the same but characters are
    not displayed.
(2) Since no characters are displayed having an updated cursor is quite useless
    so in !O_PUBLIC mode just pin the pointer to the first position of field.

I observed the second behaviour in other non-ncurses terminal applications and
have choosen to imitate that, see attached patch.

Regards,
Leon

ncurses-cursor-nonpublic-field.patch
Description: Text Data