added social icons for marketing pages

--HG--
branch : kf-captions

marketing.html

@@ -98,7 +98,20 @@ function postJSON(url, data, callback) {
         <li><a href="/t/honor.html">Honor Code</a></li>
         <li><a href="/t/mitx_help.html">Help</a></li>
       </ul>
+
+      <ul class="social">
+        <li class="linkedin">
+          <a href="http://www.linkedin.com/groups/Friends-Alumni-MITx-4316538">Linked In</a>
+        </li>
+        <li class="twitter">
+          <a href="https://twitter.com/#!/MyMITx">Twitter</a>
+        </li>
+        <li class="facebook">
+          <a href="http://www.facebook.com/pages/MITx/378592442151504">Facebook</a>
+        </li>
+      </ul>
     </div>
+
   </footer>
 
 % if settings.COURSEWARE_ENABLED:

sass/index/_footer.scss

@@ -52,6 +52,40 @@ footer {
         }
 
       }
+
+      &.social {
+        float: right;
+        margin-right: 60px;
+        position: relative;
+        top: -5px;
+
+        li {
+          float: left;
+          margin-right: lh(.5);
+
+          a {
+            display: block;
+            height: 29px;
+            width: 28px;
+            text-indent: -9999px;
+          }
+
+          &:after {
+            content: none;
+            display: none;
+          }
+
+          &.twitter a {
+            background: url('/static/images/marketing/twitter.png') 0 0 no-repeat;
+          }
+          &.facebook a {
+            background: url('/static/images/marketing/facebook.png') 0 0 no-repeat;
+          }
+          &.linkedin {
+            background: url('/static/images/marketing/linkedin.png') 0 0 no-repeat;
+          }
+        }
+      }
     }
   }
 }