Improved minutes list and gallery list views ordering

I admit that ordering the minutes list and the gallery list views by date is better ordering than created and latest image uploaded. This PR fixes that. Each gallery on the gallery list view now show pictures from the start of the album, instead of from the end. I think this is more natural when the view is ordered by date.

Also fixes a bug in assertModelOrdering - existing model instances caused the function to malfunction. The fix is to simply delete all model instances before asserting.