GNU Split Screen

Notes for split screen commands

• ctrl+a shift+\ : create new vertically split window
• ctrl+a shift+s : create new horizontally split window
• ctrl+a Tab : move cursor to the other window
• ctrl+a shift+x : close current window

*Enable vertical split on Mac: http://old.evanmeagher.net/2010/12/patching-screen-with-vertical-split-in-os
* Meet bug ("pty.c:38:26: fatal error: sys/stropts.h: No such file or directory") on Fedora: http://savannah.gnu.org/bugs/?36693