turn cursor into pointer when selecting items and hightlight selected item

See merge request subugoe/emo/Qviewer!2

* feature/emo-init: (60 commits)
  DUMMY
  FEATURE bottom bar
  let projects configure item- and manifest labels ++ npm update
  FIX buttons colors in openseadragon fullscreen
  ADD ahikar specific CSS
  CHANGE default icon
  FEATURE language select menu
  FEATURE language select menu
  bugfix: json_parse in content.vue finally fixed without catch
  add pagelabel and language to infbar and metadata
  infobar: replace itemlabel by pagenumber
  npm package update
  bugfix: osd icons blurred in fullscreen mode; delete obsolete emitter
  show pagenumbers/-labels instead of items in the tree, metadata and infobar
  provide text styling on the fly for individual project needs. just 'fake-api' is missing
  bugfix: compute sequenceindex in root instance and pass it down as prop to infobar and metadata
  (re)implement support styles for the text part
  ci build failed. sass and node-sass missing
  (re)provide original support styles for the text part
  ci build failed. sass-loader missing
  ...

codecleaning: delete obsoltes; uninstall obsolete dev-dependencies; implement routing base; bugfix: content threw parse-error regarding nested promises