Add part2

intro/part2/README.md

@@ -0,0 +1,15 @@
+# Part 2
+
+This is just like last time, except `Main.elm` is now in the `src/` directory.
+
+To build everything, `cd` into the `part2/` directory and run:
+
+```shell
+elm make src/Main.elm --output elm.js
+```
+
+Then open `index.html` in your browser.
+
+## Exercise
+
+Open `src/Main.elm` in your editor and resolve the TODOs there.