anchor.diff:  if exist extensions\viewerPDF\ (
       cd extensions\viewerPDF
       call git fetch --all
  -    cd ..\..
   ) else (
       call git clone https://github.com/tagspaces/viewerPDF.git extensions\viewerPDF
  -)
  +    cd extensions\viewerPDF
  +)
  +call bower link
  +cd ..\..
   
   REM -------------------------
   REM viewerText
  
positive.code: if exist extensions\viewerImage\ (
      cd extensions\viewerImage
      call git fetch --all
      cd ..\..
  ) else (
      call git clone https://github.com/tagspaces/viewerImage.git extensions\viewerImage
  )
  
  REM -------------------------
  REM viewerMD
  
negative.code: if exist extensions\perspectiveGrid\ (
      cd extensions\perspectiveGrid
      call git fetch --all
  ) else (
      call git clone https://github.com/tagspaces/perspectiveGrid.git extensions\perspectiveGrid
      cd extensions\perspectiveGrid
  )
  call bower link
  cd ..\..
  
  REM -------------------------
  REM perspectiveImageSwiper
  