TrackParticle eta,phi for forward electron eta,phi
Run4 forward electron reco : when there is a track match, use the track eta,phi to define the electron eta,phi, instead of the cluster eta,phi. To do this, we just run the 4Mom builder after the electron track particle has been set. This MR is just a simple reordering.
In FourMomBuilder, the relative energy resolution is used to build the covariance matrix. The corresponding parameterisation stops at |eta| = 2.4, but the code uses the last available bin when eta is out of the parameterisation range. So this matrix is not reliable for fwd electrons, at least for the time being.