Added functional flavour taggers (SSKaon, SSProton, OSKaon, OSElectron, OSMuon and OSVertexCharge) written by @cprouve, @zhshen and myself to the master branch. These are taggers ported from Run 1/2 into the Run 3 functional framework.
Moore!1836 (merged) and LHCb!3728 (merged) depends on this.