Log Message:
Update kdirstat to 2.4.4

* Improved handling of sparse files:
  Now adding up only allocated size

* Improved handling of regular files with multiple links:
  Now adding up size / no_links per occurence.
  This is much closer to what "du" reports.

* Extended "own size" column context menu to show sparse files
  and regular files with multiple links

* Reordered "own size" column context menu for consistency: xxx MB (yyy
  Bytes)

* Removed currently read path from status line while reading:
  Much less flicker, no more constant window resizing, improved performance

* Added explanations for sparse files and multiple links to online help