applied BPIX translation to BS centroid

BeamSpot Centroid as measured from fill 4008
https://virgilio.mib.infn.it/~manzoni/Run2015Beamspot/Run2015B/
BPIX position as measured here
https://hypernews.cern.ch/HyperNews/CMS/get/beamspot/134/2/1/1.html

IOMC/EventVertexGenerators/python/VtxSmearedParameters_cfi.py

@@ -424,9 +424,9 @@
     Alpha = cms.double(0.0),
     SigmaZ = cms.double(5.3),
     TimeOffset = cms.double(0.0),
-    X0 = cms.double(), # from fill 4008, absolute coordinates X0 =  0.07798 [cm]. BPix position, absolute coordinates XXX [cm]. Final position YYY [cm].
-    Y0 = cms.double(), # from fill 4008, absolute coordinates Y0 =  0.09714 [cm]. BPix position, absolute coordinates XXX [cm]. Final position YYY [cm]. 
-    Z0 = cms.double()  # from fill 4008, absolute coordinates Z0 = -1.610   [cm]. BPix position, absolute coordinates XXX [cm]. Final position YYY [cm].
+    X0 = cms.double(0.10482), # from fill 4008, absolute coordinates X0 =  0.07798 [cm]. BPix position, absolute coordinates -0.026837  [cm]. Final position  0.10482 [cm].
+    Y0 = cms.double(0.16867), # from fill 4008, absolute coordinates Y0 =  0.09714 [cm]. BPix position, absolute coordinates -0.0715252 [cm]. Final position  0.16867 [cm]. 
+    Z0 = cms.double(-1.0985)  # from fill 4008, absolute coordinates Z0 = -1.610   [cm]. BPix position, absolute coordinates -0.511453  [cm]. Final position -1.0985  [cm].
 )
 # Test HF offset
 ShiftedCollision2015VtxSmearingParameters = cms.PSet(