Acts Kalman Fitter refitting
This PR implement the Acts Kalman Fitter within athena. It also provide a ATLAS implementation of the Acts source link to be used as an input for the Fitting and a converter tool that can trasform Acts object into Athena one and vice versa. Finally it implement an Acts refitting tool that can be used to refit Atlas Track with the Acts Kalman Fitter to compare the performances.
Edited by Corentin Allaire