[KPhotoAlbum] Message on renaming categories

[Tobias Leupold]

> Someone please clarify me how this works and what should I press and then
> try also to clarify the text..

Risto, would you please checkout the recently added v6update branch and have a 
look at it with an old (v4 or v5) database? I tried to make all this more 
clear, both if you choose the update (that's what everybody really should) and 
not.

I'd be glad to get some feedback :-)

Cheers, Tobias