fixed parts rescaling - 2nd try - CORRECTED my own error

Fixes incorrect rescaling of parts, containing "scale" in MODEL
description. !!second try- CORRECTED my own error!!
For example, many of KW Rocketry parts

http://forum.kerbalspaceprogram.com/threads/51037-0-24-2-KW-Rocketry-v2-6c-Available-New-5m-Parts!-24-07-2014
or Cubic Trusses from Spherical and Toroidal Tank Pack by
Talisar
http://forum.kerbalspaceprogram.com/threads/30673-0-23-5-Spherical-and-Toroidal-Tank-Pack-%28Updated-05-02-14%29-%28New-download-link%29