*Small refinements to the grouptagsettingsdialog.
*Groups can be tagged.
*Tagging of files only if they exist -- note: no tagging of .part files yet as the tags do not get moved other when the download is finished.
*Remove an aborted KIO download a way that associated tags would also be removed.

svn path=/trunk/KDE/kdenetwork/kget/; revision=962597