adds emacs docs to quit and open file

pages/common/emacs.md

@@ -2,6 +2,14 @@
 
 > The extensible, customizable, self-documenting, real-time display editor
 
-- open emacs in console mode (without X window)
+- Open emacs in console mode (without X window)
 
 `emacs -nw`
+
+- Open a file in emacs
+
+`emacs {{filename}}`
+
+- Exit emacs
+
+`C-x C-c`