Fix in Gullberg implementation. Test had not been carried out with detector not at the isocenter.
Fix in Gullberg implementation. Test had not been carried out with
detector not at the isocenter.

SimonRit/RTK,ipsusila/RTK,ldqcarbon/RTK,ipsusila/RTK,fabienmomey/RTK,ldqcarbon/RTK,fabienmomey/RTK,ipsusila/RTK,SimonRit/RTK,SimonRit/RTK,ldqcarbon/RTK,dsarrut/RTK,ipsusila/RTK,ipsusila/RTK,dsarrut/RTK,dsarrut/RTK,ipsusila/RTK,dsarrut/RTK,dsarrut/RTK,fabienmomey/RTK,dsarrut/RTK,fabienmomey/RTK,fabienmomey/RTK,ldqcarbon/RTK,ldqcarbon/RTK,fabienmomey/RTK,dsarrut/RTK,ipsusila/RTK,SimonRit/RTK,fabienmomey/RTK,ldqcarbon/RTK,ldqcarbon/RTK