Using --zap or -Z on the command line, or 'set zap' in a nanorc file,
makes the <Bsp> and <Del> keys erase selected text (a marked region)
as they do in some other editors, and without affecting the cutbuffer.
This fulfills https://savannah.gnu.org/bugs/?54837.
Requested-by: Liu Hao <lh_mouse@126.com>
Signed-off-by: Brand Huntsman <alpha@qzx.com>
ae3ec1784d