Update Exercises Directory Names to Reflect Order

exercises/12_options/options3.rs

@@ -0,0 +1,21 @@
+// options3.rs
+//
+// Execute `rustlings hint options3` or use the `hint` watch subcommand for a
+// hint.
+
+// I AM NOT DONE
+
+struct Point {
+    x: i32,
+    y: i32,
+}
+
+fn main() {
+    let y: Option<Point> = Some(Point { x: 100, y: 200 });
+
+    match y {
+        Some(p) => println!("Co-ordinates are {},{} ", p.x, p.y),
+        _ => panic!("no match!"),
+    }
+    y; // Fix without deleting this line.
+}