readd get_byte_kbinput(), modify get_word_kbinput() to handle

readd get_byte_kbinput(), modify get_word_kbinput() to handle
hexadecimal instead of decimal values, make normal input use
get_byte_kbinput(), make verbatim input use get_word_kbinput(), and
update faq.html to mention these changes

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@2221 35c25a1d-7b9e-4130-9fde-d3aeb78583b8