Add windresize.el to GNU ELPA.

windresize.el lets the user manipulate windows quickly
through simple keystrokes.
Added packages/windresize/windresize.el to GNU ELPA.

windresize.el provides commands to quickly manipulate
windows.
windresize.el: Make the commentary more informative.
Fix version numbers of sisu-mode, register-list, and windresize.
* admin/update-archive.sh: Keep old packages.