implement cutting from the current position to the end of the file,

implement cutting from the current position to the end of the file,
using Ctrl-X from the search prompt and Meta-T from the edit window;
also update the copyright years of more modified files

git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@2211 35c25a1d-7b9e-4130-9fde-d3aeb78583b8