Add label for drafts in the UI

This makes it easier to see what a blog will look like when it's
published, and decreases the possibility of confusion when trying to
publish a post.

layouts/partials/li.html

@@ -1,4 +1,8 @@
 <li class="post-item">
     <span class="meta">{{ .Date.Format .Site.Params.dateform }}</span>
+    {{ if .Params.draft }}
+    <a href="{{ .Permalink }}"><span>Draft::{{ .Title }}</span></a>
+    {{ else }}
     <a href="{{ .Permalink }}"><span>{{ .Title }}</span></a>
+    {{ end }}
 </li>

layouts/partials/page-heading.html

@@ -2,6 +2,10 @@
 {{ if .Params.heading }}
     {{ .Params.heading }}
 {{ else }}
+    {{ if .Params.draft }}
+    Draft::{{ .Title }}
+    {{ else }}
     {{ .Title }}
+    {{ end }}
 {{ end }}
 </div>