fix main docs nav to use latest navbar changes

docs/_includes/nav-home.html

-<header class="navbar navbar-sm navbar-defeault navbar-static-top bd-navbar" role="banner">
-  <div class="container-fluid">
-    <nav class="nav nav-inline pull-right">
+<header class="navbar navbar-light navbar-static-top bd-navbar" role="banner">
+  <nav class="nav navbar-nav pull-right">
     <div class="nav-item dropdown">
       <a class="nav-item nav-link dropdown-toggle" href="#" id="bd-versions" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
         v{{ site.current_version }}
@@ -22,12 +21,11 @@
       </div>
     </div>
   </nav>
-    <nav class="nav nav-inline">
+  <nav class="nav navbar-nav">
     <a class="nav-item nav-link {% if page.layout == "home" %}active{% endif %}" href="{{ site.baseurl }}/" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Bootstrap');">Bootstrap</a>
     <a class="nav-item nav-link {% if page.layout == "docs" %}active{% endif %}" href="{{ site.baseurl }}/getting-started/introduction/" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Docs');">Documentation</a>
     <a class="nav-item nav-link {% if page.title == "Examples" %}active{% endif %}" href="{{ site.baseurl }}/examples/" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Examples');">Examples</a>
     <a class="nav-item nav-link" href="{{ site.expo }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Expo');">Expo</a>
     <a class="nav-item nav-link" href="{{ site.blog }}" onclick="ga('send', 'event', 'Navbar', 'Community links', 'Blog');">Blog</a>
   </nav>
-  </div>
 </header>

docs/assets/scss/_nav.scss

@@ -3,11 +3,7 @@
 //
 
 .bd-navbar {
-  padding-top: 1rem;
-  padding-bottom: 1rem;
-  margin-bottom: 0;
-  // background-color: $bd-graphite;
-
+  .navbar-nav {
     .nav-link {
       color: $bd-graphite-light;
 
@@ -22,4 +18,5 @@
         font-weight: 500;
       }
     }
+  }
 }