add initial attempt at adding winit example

examples/winit/README.md

@@ -0,0 +1,18 @@
+## Counter
+
+The classic counter example explained in the [`README`](../../README.md).
+
+The __[`main`]__ file contains all the code of the example.
+
+<div align="center">
+  <a href="https://gfycat.com/fairdeadcatbird">
+    <img src="https://thumbs.gfycat.com/FairDeadCatbird-small.gif">
+  </a>
+</div>
+
+You can run it with `cargo run`:
+```
+cargo run --package counter
+```
+
+[`main`]: src/main.rs