Refactor jumbotron into partial

All jumbotrons now use the same code.
Jumbotron will detect if it is being loaded on the home page and load
information accordingly.
Signed-off-by: Ethan Madison <ethan@ethanmad.com>

layouts/_default/single.html

 {{ partial "header.html" . }}
 
-<div class="jumbotron">
-    <div class="container">
-        <h1>{{ .Title }}</h1>
-        <p>{{ with .Params.description }}{{ . }}{{ end }}</p>
-    </div>
-</div>
-
+{{ partial "jumbotron.html" . }}
 <div class="container">
 <div class="row">
 	<div class="col-sm-8 doc-main">

layouts/index.html

@@ -3,12 +3,7 @@
 
 <main role="main">
 
-<div class="jumbotron">
-    <div class="container">
-        <h1>{{ .Site.Title }}</h1>
-        <p>{{ if isset .Site.Params "description" }}{{ .Site.Params.description }}{{ else }}You can customize this text by params "description" in your <code>config.toml</code>.{{ end }}</p>
-    </div>
-</div>
+{{ partial "jumbotron.html" . }}
 
 <div class="container">
 <div class="row">

layouts/partials/jumbotron.html

+{{ $isHomePage := eq .Title .Site.Title }}
+
+<div class="jumbotron">
+    <div class="container">
+        <h1>{{ if $isHomePage }}{{ .Site.Title }}{{ else }}{{ .Title }}{{ end }}</h1>
+        <p>{{ if $isHomePage }}{{ with .Site.Params.description }}{{ . }}{{ end }}{{ else }}{{ with .Params.description }}{{ . }}{{ end }}{{ end }}</p>
+    </div>
+</div>