[KPhotoAlbum] Cannot run Demo

[Andreas Schleth]

Just now, I built KPA (git master) on a new system.
This was the very first install on this machine, so no prior installs 
from other sources.

KPA does not load/find the demo database.

The demo resides in /usr/local/share/... by default.

KPA searches in ~/.local/usr/share/... and in /usr/share/... and thus 
misses the default path.

This will only hit first time installers, as most others (developers) 
will have multiple demo dbs around.

Andreas