various input/output fixes: allow normal typing of high-bit control

various input/output fixes: allow normal typing of high-bit control
characters, as Pico does; in do_verbatim_input(), unconditionally blank
the statusbar as soon as we're finished getting input; and in
parse_verbatim_kbinput(), don't include the ability to enter a Unicode
sequence via verbatim input mode if ENABLE_UTF8 isn't defined

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@3584 35c25a1d-7b9e-4130-9fde-d3aeb78583b8