Duplicate detection in import process

[Alvaro del Castillo <acs openshine com>]

Hi guys!

Finally I have implemented the main feature about photo duplicates
detection: detect the duplicate when importing photos in F-Spot. You can
see the a video-demo in:

http://acs.barrapunto.org/~acs/FSpotDuplicates.html

All the code is for now in my subversion repository in:

https://acs.barrapunto.org/svn/f-spot/

if you want to play with it. It is synced with actual F-Spot CVS so if
it is decided to include the feature in F-Spot CVS, it should be easy.

The way it is implemented control all the import commands, including the
Flickr and Web Gallery imports.

Also, if you have already duplicate photos imported, you can use the
Find Duplicates menu entry to detect them. The new implementation is
faster.

Cheers

-- Alvaro