Add OpenGraph tags

source/index.html.erb

@@ -1,5 +1,5 @@
 ---
-title: Persephone
+title: Persephone – A modern, open source MPD client for macOS
 ---
 
 <header role="banner">
@@ -31,7 +31,7 @@ title: Persephone
   </div>
 
   <div class="download-section">
-    <a class="download-button" href="https://f001.backblazeb2.com/file/persephone/Persephone-0.15.2-alpha.zip">↓ Download 0.15.2-alpha</a>
+    <a class="download-button" href="https://f001.backblazeb2.com/file/persephone/Persephone-0.16.0-alpha.zip">↓ Download 0.16.0-alpha</a>
   </div>
 
   <picture class="screenshot">

source/layouts/layout.erb

@@ -6,8 +6,12 @@
     <meta name="viewport"
           content="width=device-width, initial-scale=1, shrink-to-fit=no">
     <!-- Use the title from a page's frontmatter if it has one -->
-    <title><%= current_page.data.title || "Middleman" %></title>
+    <title><%= current_page.data.title %></title>
     <link rel="stylesheet" type="text/css" href="https://cloud.typography.com/7434852/6168012/css/fonts.css" />
+    <meta property="og:title" content="<%= current_page.data.title %>" />
+    <meta property="og:type" content="website" />
+    <meta property="og:url" content="https://persephone.fm" />
+    <meta property="og:image" content="https://persephone.fm/images/og.png" />
     <%= stylesheet_link_tag "site" %>
     <%= javascript_include_tag "site" %>
   </head>