add fibonacci example

docs/examples/fibonacci/index.js

@@ -0,0 +1,9 @@
+function fib(n) {
+  if(n == 0 || n == 1) {
+    return n
+  } else {
+    return fib(n - 1) + fib(n - 2)
+  }
+}
+
+fib(6)

src/examples.js

@@ -11,6 +11,10 @@ export const examples = [
     path: 'github_api',
     entrypoint: 'github_api/index.js',
   },
+  {
+    path: 'fibonacci',
+    entrypoint: 'fibonacci/index.js',
+  },
   {
     path: 'todos-preact',
     entrypoint: 'todos-preact/index.js',