More frontend fixes

- added key handling for draggable dropnav
- added stacks entry to menu
- added info when no page is available
- added some basic touch support
- open first page within sidebar
- fixes modal window title
- fixes modal window initial size (fit to browser size)
- fixes issue with multiple ids (same stacks)
- fixes advanced settings switch
- fixes "esc" on modal when focused
- css improvements
- fixes minor ui issues