fix cFit bug, update personalities


git-svn-id: svn+ssh://svn.cern.ch/reps/lhcb/Urania/trunk/PhysFit/B2DXFitters@173505 4525493e-7705-40b1-a816-d608a930855b
protect against numerical pathologies


git-svn-id: svn+ssh://svn.cern.ch/reps/lhcb/Urania/trunk/PhysFit/B2DXFitters@173518 4525493e-7705-40b1-a816-d608a930855b
fix small bug


git-svn-id: svn+ssh://svn.cern.ch/reps/lhcb/Urania/trunk/PhysFit/B2DXFitters@173544 4525493e-7705-40b1-a816-d608a930855b