Link to trending public projects so more relevant projects are shown to new users.

app/views/dashboard/_zero_authorized_projects.html.haml

@@ -46,5 +46,5 @@
         %br
         Public projects are an easy way to allow everyone to have read-only access.
       .link_holder
-        = link_to explore_projects_path, class: "btn btn-new" do
+        = link_to trending_explore_projects_path, class: "btn btn-new" do
           Browse public projects »