[pitivi] (16 commits) ...Merging translations

[Edward Hervey <edwardrv src gnome org>]

Summary of changes:

  b6d4a5c... Add a "zoom fit" button near the zoom slider
  1c20045... Make the zoom slider a reasonable minimum width
  81a3344... Make MainWindow.setBestZoomRatio public
  2146bca... Properly call mainwindow's setBestZoomRatio()
  5de81c0... Add a menu item for zoom fit
  e669902... Make the layers/tracks controls fill available space
  dce4a45... Replace the sourcelist busy animation by a progressbar.
  ca7c51a... Kill the infostub widget and replace it with a progressbar 
  fae567c... Usability fixes for the FileListError dialog
  3f7226d... Auto-expand the first two errors in FileListErrorDialog
  b8664d8... Make the URIs in FileListErrorDialog human-readable
  ec60d28... Fix the total amount of clips being imported when loading a
  fd58be7... Handle plurals and singular for the warning infobar's label
  fa0f82a... ui/sourcelist Code cleanup
  bbd1871... sourcelist: Add a button to hide the error infobar
  b0c7f6c... Merging translations