client/tags: quicker access to the tagged posts

Based on #656, plus escaping.

client/html/tags_page.tpl

@@ -71,7 +71,7 @@
                             <% } %>
                         </td>
                         <td class='usages'>
-                            <%- tag.postCount %>
+                            <a href='<%- ctx.formatClientLink('posts', {query: ctx.escapeTagName(tag.names[0])}) %>'><%- tag.postCount %></a>
                         </td>
                         <td class='creation-time'>
                             <%= ctx.makeRelativeTime(tag.creationTime) %>

client/js/util/views.js

@@ -460,6 +460,7 @@ function getTemplate(templatePath) {
             makeCssName: misc.makeCssName,
             makeNumericInput: makeNumericInput,
             formatClientLink: uri.formatClientLink,
+            escapeTagName: uri.escapeTagName,
         });
         return htmlToDom(templateFactory(ctx));
     };