Fixed a bug where the thumbnails were not improved after a repack().   Also, timing repacks.
Fixed a bug where the thumbnails were not improved after a repack().  
Also, timing repacks.


abrauchli/shotwell,jimbonator/shotwell,ritchiewilson/shotwell,damianmoore/shotwell,damianmoore/shotwell,jof/shotwell,polymeris/shotwell,ritchiewilson/shotwell,Sanva/shotwell-gsoc,jof/shotwell,jimbonator/shotwell,jof/shotwell,damianmoore/shotwell,h4ck3rm1k3/shotwell,Sanva/shotwell-gsoc,abrauchli/shotwell,ritchiewilson/shotwell,polymeris/shotwell,polymeris/shotwell,jimbonator/shotwell,Sanva/shotwell-gsoc,h4ck3rm1k3/shotwell,abrauchli/shotwell,h4ck3rm1k3/shotwell