Fix UI bug introduced in new project page

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/stylesheets/pages/projects.scss

@@ -432,7 +432,7 @@ pre.light-well {
   }
 }
 
-.prepend-top-20 {
+.project-footer {
   margin-top: 20px;
 
   .btn-remove {

app/views/projects/show.html.haml

@@ -75,7 +75,7 @@
 - if current_user
   - access = user_max_access_in_project(current_user, @project)
   - if access
-    .prepend-top-20
+    .prepend-top-20.project-footer
       .gray-content-block.footer-block.center
         You have #{access} access to this project.
         - if @project.project_member_by_id(current_user)