ksh: add page (#2620)

pages/common/ksh.md

@@ -0,0 +1,20 @@
+# ksh
+
+> Korn Shell.
+> `bash` and `sh`-compatible command line interpreter.
+
+- Start interactive command line interpreter:
+
+`ksh`
+
+- Execute a command:
+
+`ksh -c {{command}}`
+
+- Run commands from a file:
+
+`ksh {{file}}`
+
+- Run commands from a file and print them as they are executed:
+
+`ksh -x {{file}}`