Adds right-sidebar navigation made available in #475 to Blog Post pag…

…es (#682)

lib/core/BlogPostLayout.js

@@ -10,6 +10,7 @@ const BlogPost = require('./BlogPost.js');
 const BlogSidebar = require('./BlogSidebar.js');
 const Container = require('./Container.js');
 const Site = require('./Site.js');
+const OnPageNav = require('./nav/OnPageNav.js');
 const utils = require('./utils.js');
 
 // used for entire blog posts, i.e., each written blog article with sidebar with site header/footer
@@ -127,6 +128,11 @@ class BlogPostLayout extends React.Component {
               </a>
             </div>
           </Container>
+          {this.props.config.onPageNav == 'separate' && (
+            <nav className="onPageNav">
+              <OnPageNav rawContent={this.props.children} />
+            </nav>
+          )}
         </div>
       </Site>
     );