Fix project create link on group page

app/views/groups/_projects.html.haml

@@ -2,7 +2,7 @@
   .panel-heading.clearfix
     .input-group
       = search_field_tag :filter_projects, nil, placeholder: 'Filter by name', class: 'projects-list-filter form-control'
-      - if current_user.can_create_project?
+      - if can? current_user, :create_projects, @group
         .input-group-addon.dash-new-project
           = link_to new_project_path(namespace_id: @group.id) do
             %strong New project