Log message:
misc/screen4: import screen-4.9.1

Screen is a full-screen window manager that multiplexes a physical terminal
between several processes (typically interactive shells).
Each virtual terminal provides the functions of a DEC VT100 terminal and, in
addition, several control functions from the ANSI X3.64 (ISO 6429) and ISO
2022 standards (e.g. insert/delete line and support for multiple character
sets). There is a scrollback history buffer for each virtual terminal and a
copy-and-paste mechanism that allows moving text regions between windows.

misc/screen-5.0.0 does not work under xterm. Reversed strings are
not displayed properly at least. Import working GNU screen 4 as
misc/screen4. And screen-5.0.0 does not have codes for older platforms.