Update the current NGC catalog to a new updated one for Stellarium

The NGC catalog used in Stellarium currently has many mistakes. I had the very kind permission from Wolfgang Steinicke to use his updated NGC and IC catalogs available from his web site: http://www.klima-luft.de/steinicke/ngcic/rev2000/Explan.htm His catalog provide more accurate positions, merge doublons etc.. He a...