Collapsing tree into more sane Go project layout

since I was in here looking at something unrelated...

gotime/gotour-artifacts/exercise-fibonacci-closure/main.go

@@ -0,0 +1,23 @@
+package main
+
+import "fmt"
+
+// fibonacci is a function that returns
+// a function that returns an int.
+func fibonacci() func() int {
+	prev := 0
+	cur := 1
+	return func() int {
+		old_cur := cur
+		cur = prev + cur
+		prev = old_cur
+		return cur
+	}
+}
+
+func main() {
+	f := fibonacci()
+	for i := 0; i < 10; i++ {
+		fmt.Println(f())
+	}
+}