fix typo

app/views/layouts/project.html.haml

@@ -26,7 +26,7 @@
                   - if @project.users_projects.count > 0
                     %span{ :class => "number" }= @project.users_projects.count
                 = link_to  project_issues_path(@project), :class => (controller.controller_name == "issues") ? "current" : nil do
-                  Issuess
+                  Issues
                   - if @project.issues.opened.count > 0
                     %span{ :class => "number" }= @project.issues.opened.count
                 = link_to wall_project_path(@project), :class => current_page?(:controller => "projects", :action => "wall", :id => @project) ? "current" : nil do