adding Apache conference promo to home page

docs/_static/mxnet-theme/index.html

@@ -1,8 +1,8 @@
 <div id="splash">
   <div class="container">
     <div class="row">
-      <div class="col-lg-12">
-          <div id="banner-title" class='col-sm-6 col-xs-12'><span>Apache MXNet (Incubating)</span>
+      <div class="col-lg-6">
+          <div id="banner-title"><span>Apache MXNet (Incubating)</span>
             <p id="landing-title">A flexible and efficient library for deep learning.</p>
             <div id='landing-btn-blk'>
                 <div id="install_blk">
@@ -12,7 +12,10 @@
                     <a href="faq/why_mxnet.html" id="why_mxnet_btn">Learn More</a>
                 </div>
             </div>
-        </div>
+          </div>
+      </div>
+      <div class="col-lg-6" style="padding-top: 60px;">
+        <a href="http://www.apachecon.com/acna18/" class="section-tout-promo"><img src="http://www.apachecon.com/acna18/banners/acna-sleek-highres.png" width="65%" alt="apachecon"/></a>
       </div>
     </div>
   </div>
@@ -31,10 +34,10 @@ <h3>MXNet 1.2.1 Released</h3>
         <a href="https://github.com/apache/incubator-mxnet/releases/tag/1.2.1">Learn More</a>
       </div>
       <div class="col-lg-4 col-sm-12">
-          <h3>Introducing the Scala Inference API</h3>
-          <p>A model loading and inference API is now available for Scala developers. Try out the examples for single shot detection and loading models for image classification.
-          </p>
-          <a href="api/scala/index.html">Learn More</a>
+        <h3>Introducing the Scala Inference API</h3>
+        <p>A model loading and inference API is now available for Scala developers. Try out the examples for single shot detection and loading models for image classification.
+        </p>
+        <a href="api/scala/index.html">Learn More</a>
       </div>
     </div>
   </div>