added stopwatch example

added requestAnimationFrame polyfill

moved raf logic into a subscription

separated logic into multiple files, all state lives in a global namespaced model, reset no longer sends multiple actions only one

examples/stopwatch/views/main.js

@@ -0,0 +1,36 @@
+const html = require('../../../html')
+const format = require('../utilities/format')
+
+function toggle (state, send) {
+  if (state.start) {
+    send('stop')
+  } else {
+    send('start')
+  }
+}
+
+module.exports = (state, prev, send) => {
+  const start = state.start
+  const elapsed = state.elapsed
+
+  return html`
+    <main class="app">
+      <h1>stopwatch</h1>
+      <p>${format(elapsed)}</p>
+      <button 
+        onclick=${e => toggle(state, send)}
+        >${start ? 'stop' : 'start'}</button>
+      <button 
+        style="display:${start ? 'none' : 'inline'};" 
+        onclick=${e => send('reset')}
+        >reset</button>
+      <button 
+        style="display:${start ? 'inline' : 'none'};" 
+        onclick=${e => send('add', format(elapsed))}
+        >lap</button>
+      <ol>
+        ${state.laps.map(lap => html`<li>${lap}</li>`)}
+      </ol>
+    </main>
+  `
+}