in do_replace_loop(), when moving to the next match, update the screen

in do_replace_loop(), when moving to the next match, update the screen
using edit_refresh() instead of edit_redraw(), as the latter won't work
properly when we've replaced one or more instances of a string in copy
and haven't yet updated current->data to match copy

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@2599 35c25a1d-7b9e-4130-9fde-d3aeb78583b8