Move jacobian calculation to DF

This PR moves the simple jacobian matrix definition from TrackingTools to DataFormats.
With this change we can properly compute the uncertainty on sum of Candidates as needed by btag for VertexCompositePtrCandidate.
(The fix for VertexCompositePtrCandidate wrt original Dinko's implementation will be in a separate later PR)

@ferencek @VinInn 
given the presence of R and of theJacobian * R;
most probably yes...
Of course we should remove the use of the old class and use the function in the few places where is used..
Cartesian errors are not used in Tracking...  only in vertex fitting