client/posts: support content aware post flow option

client/html/posts_page.tpl

@@ -1,4 +1,4 @@
-<div class='post-list'>
+<% if (ctx.postFlow) { %><div class='post-list post-flow'><% } else { %><div class='post-list'><% } %>
     <% if (ctx.response.results.length) { %>
         <ul>
             <% for (let post of ctx.response.results) { %>

client/html/settings.tpl

@@ -47,6 +47,15 @@
                 <p class='hint'>Rather than using a paged navigation, smoothly scrolls through the content.</p>
             </li>
 
+            <li>
+                <%= ctx.makeCheckbox({
+                    text: 'Use post flow',
+                    name: 'post-flow',
+                    checked: ctx.browsingSettings.postFlow,
+                }) %>
+                <p class='hint'>Use a content-aware flow for thumbnails on the post search page.</p>
+            </li>
+
             <li>
                 <%= ctx.makeCheckbox({
                     text: 'Enable transparency grid',