added empty css/cx_open_list.css file
added empty css/cx_open_list.css file

git-svn-id: 9343c33165826e1b83ce54045b3fd54508162d01@29623 ee427ae8-e902-0410-961c-c3ed070cd9f9

Symfony-Plugins/cxFormExtraPlugin,Symfony-Plugins/cxFormExtraPlugin