begining of a VLM interface and some code organisations changes. The vlm

begining of a VLM interface and some code organisations changes. The vlm
interface should be done pretty soon (i'll try to finish it tomorrow)

 vlm.html : vlm web interface. What works: sending broadcast and vod creation
            commands

 js/vlm.js : add code to handle sending vlm commands.

 requests/vlm_cmd.xml : used to send a vlm command and get the resulting
                        error message

 requests/vlm.xml : export the full vlm media/schedules "tree". I still need
                    to parse that in js/vlm.js in order to display it in
                    dialogs/vlm .

 dialogs/* : dialogs' code which is used as building blocks for the
             main pages. (in order to avoid code duplication)

 mosaic.html, js/mosaic.js, dialogs/mosaic : start of a mosaic help
            page. nothing works and it's almost empty but i didn't feel like
            sorting through the commited files.