fix inefficent communication between server and workspace during filelisting for preview purpose
 enable multiple instances of codeeditor executing code simultanious
 transmit execution information (start, output, end) via bus instead of poll
 output shows up immediately
 codeeditor will immediatly be notified about external changes (modify,delete,move) by bus instead of polling
 previewtab will immediatly be notified about changes in the currently displayed folder by bus instead of polling
 some small changes