added proper head tags and second level header text to the site header

Author: Chris McLean

app/index.html

@@ -29,7 +29,10 @@
             <div class="navbar navbar-default" role="navigation">
                 <div class="container">
                     <div class="row">
-                        <div class="navbar-header"><a class="navbar-brand" href="#">Crunchinator</a></div>
+                        <div class="navbar-header">
+                            <h1><a class="navbar-brand" href="#">Crunchinator</a></h1>
+                            <h2>Crunchbase search and visualization built using Angular.js and D3.</h2>
+                        </div>
                     </div>
                 </div>
             </div>