pyside-lupdate destroys user data in TS files

The attached example TS file was created by linguist 4.7.2, and adheres to the TS DTD at http://doc.qt.digia.com/stable/linguist-ts-file-format.html. It makes use of length variants and translator comments. If the TS file is updated (using `pyside-lupdate example.py -ts hu_HU.ts`), the comments and all but one variant translation are lost. The remaining translation will have an unwanted newline.

(Note: Running the example script will never display the translated text, due to a yet-to-be-filed bug regarding inheritance.)