Move yoga docs into docs folder on master branch

Summary: Move yoga docs into master branch so that pull requests are able to include doc updates as part of other changes.

Reviewed By: JoelMarcey

Differential Revision: D4365700

fbshipit-source-id: 2f46a88974104c454c00bcdf1257abb5c4075a68

docs/_includes/home_header.html

@@ -0,0 +1,31 @@
+<div class="homeContainer">
+  <div class="homeSplashFade">
+    <div id="home_wrap" class="wrapper homeWrapper">
+      <div id="inner">
+        <h2 id="project_tagline">{{ site.tagline }}</h2>
+        <section id="intro">
+          <!--<p>{% if page.excerpt %}{{ page.excerpt | strip_html }}{% else %}{{ site.description }}{% endif %}</p>-->
+          <p>
+            Yoga is a cross-platform layout engine enabling maximum collaboration within your team by implementing an API familiar to many designers and opening it up to developers across different platforms.
+          </p>
+          <ul>
+            <li>Do you already know Flexbox? Then you already know Yoga.</li>
+            <li>Write code in a language familiar to you - Java, C#, Objective-C, C.</li>
+            <li>C under the hood so your code moves fast.</li>
+            <li>Battle tested in popular frameworks like React Native.</li>
+          </ul>
+        </section>
+        <div id="promo" class="section promoSection">
+          {% for promo in site.data.promo %}
+            <div class="promoRow">
+            {% include plugins/{{promo.type}}.html href=promo.href text=promo.text children=promo.children %}
+            </div>
+          {% endfor %}
+        </div>
+      </div>
+      <div class="projectLogo">
+        <img src="{{ '/static/logo.svg' | relative_url }}" alt="{{ site.title }}">
+      </div>
+    </div>
+  </div>
+</div>