add simple Hello "world"

_example/simple/simple.go

@@ -0,0 +1,19 @@
+package main
+
+import (
+	"io"
+	"log"
+
+	"github.com/hloeffler/ssh"
+)
+
+func main() {
+
+	ssh.Handle(func(s ssh.Session) {
+		user := s.User()
+		io.WriteString(s, "Hello "+user+"\n")
+	})
+
+	log.Fatal(ssh.ListenAndServe(":2222", nil))
+
+}