widgets: Fix project filter buttons (#362)

layouts/partials/widgets/projects.html

@@ -15,7 +15,8 @@
     <span class="hidden default-project-filter">{{ (index $page.Params.filter ($filter_default)).tag }}</span>
     {{ end }}
 
-    {{ if and (($page.Params.filter) (gt (len $page.Params.filter) 1)) }}
+    {{ if isset $page.Params "filter" }}
+    {{ if gt (len $page.Params.filter) 1 }}
     <div class="project-toolbar">
       <div class="project-filters">
         <div class="btn-toolbar">
@@ -28,6 +29,7 @@
       </div>
     </div>
     {{ end }}
+    {{ end }}
 
     {{ if eq $page.Params.view 0 }}