new headers, ad placements, intro paragraphs on several pages, etc

docs/components/button-dropdown.md

@@ -3,7 +3,7 @@ layout: page
 title: Button dropdown
 ---
 
-Use any button to trigger a dropdown menu by placing it within a `.btn-group` and providing the proper menu markup.
+Use any button to trigger a dropdown menu by placing it within a `.btn-group` and providing the proper dropdown menu markup.
 
 <div class="bs-callout bs-callout-danger">
   <h4>Plugin dependency</h4>

docs/components/jumbotron.md

@@ -5,6 +5,8 @@ title: Jumbotron
 
 A lightweight, flexible component that can optionally extend the entire viewport to showcase key marketing messages on your site.
 
+## Example
+
 {% example html %}
 <div class="jumbotron">
   <h1 class="jumbotron-heading">Hello, world!</h1>

docs/components/page-header.md

@@ -5,6 +5,8 @@ title: Page header
 
 A simple shell for an `h1` to appropriately space out and segment sections of content on a page. It can utilize the `h1`'s default `small` element, as well as most other components (with additional styles).
 
+## Example
+
 {% example html %}
 <div class="page-header">
   <h1>Example page header <small>Subtext for header</small></h1>