New user terminal settings weren't display/settable durin sign-up

The interactive prompting for terminal capabilities worked fine,
but the default configuration menu settings did not reflect the
user's previous choices and changes they made (e.g. toggle mouse
support or BS/DEL key swap) were not reflected in the menu. Once
logged in, the normal user defaults menu worked as expected. This
is all because term_supports() keyed off of SS_USERON which isn't
set during new user sign-up, so let's key off SS_USERON|SS_NEWUSER
now.