Add slider test component

spec/components/slider.cjsx

@@ -0,0 +1,13 @@
+Slider = require '../../components/slider'
+
+module.exports = React.createClass
+  render: ->
+    <section>
+      <h2>Sliders</h2>
+      <p>Normal slider</p>
+      <Slider />
+      <p>With steps, initial value and editable</p>
+      <Slider value={5} min={0} max={10} editable />
+      <p>Pinned and with snaps</p>
+      <Slider pinned snaps value={1} min={0} max={10} step={1} editable />
+    </section>