NHL: Pavol Demitra to the KHL, other signings F Pavol Demitra is headed to the KHL to play for the Lokomotiv Yaroslavl (1 year, TBA) C Mikko Koivu signs an extension with the Minnesota Wild (7 years, 47.25M) D Derek Meech signs with the Detroit Red Wings (1 year, TBA) F Gregory Campbell signs with…