Important modification in mediaitem_detail page, which loads in parallel with the...

Important modification in mediaitem_detail page, which loads in parallel with the player setup, allowing to visualize the page immediately. The player setup, on the other hand, loads function in series: analyzer->player->markers, allowing to have control over the load chain, eg, display error messages etc... Moreover, decreased the number of javascript files to load (controller also can be removed, graphics maybe), fixed some bug relative to popup and playerlist, added "add to playlist" to each markerdiv. Still to be set the focus on each div, and to (possibly) modify mediaitm_detail template, as the submenudiv has problems with the new content_header div when in edit or copy mode