On delete, actually delete file from file system

Needed for sigurdga#12 and sigurdga#14

Author: sigurdga

fileupload/models.py

@@ -17,3 +17,7 @@ def get_absolute_url(self):
     def save(self, *args, **kwargs):
         self.slug = self.file.name
         super(Picture, self).save(*args, **kwargs)
+
+    def delete(self, *args, **kwargs):
+        self.file.delete(False)
+        super(Picture, self).delete(*args, **kwargs)