[KPhotoAlbum] Breaking changes in file layout

[Johannes Zarl-Zierl]

Am Montag, 6. April 2020, 00:22:30 CEST schrieb Robert Krawitz:
> On Sun, 05 Apr 2020 23:50:29 +0200, Johannes Zarl-Zierl wrote:
> >> One thing I'd like to think about is how kpa could work with multiple
> >> users accessing a read-only collection of images.  That would mean at
> >> least the ability to separate these files from the actual image
> >> storage.
> > 
> > Having a read-only database alongside a read-only collection of
> > images shouldn't pose a problem with the proposed scheme.
> 
> I'm thinking a read/write database with read-only images.

It seems I forgot to pick this up yesterday. A read/write database with read-
only images would only be feasible if we move the database into ~/.local/
share.
KPhotoAlbum has always handled the index.xml directory and the image directory 
as synonymous. I'm against changing that for now.
You can still achieve this setup in multiple ways, though. The most obvious 
being:
mkdir ~/Pictures # index.xml resides here
ln -s /my/readonly/mountpoint ~/Pictures