Use new functionals for neutrals

New functionals for photons and merged pi0s are being added at Phys!756 (merged).

These functionals are adapted to the new Gaudi framework, where explicit input/output declaration and thread-safety are imposed. They are compatible with the reconstruction switch between "reco from file" and "reco on the fly". No changes are needed for any line: the wrappers have been changed to use the new functionals while keeping the same syntax.

Radiative lines have been re-inserted in the test.

There is an issue with the docs pipe, I don't know if it is expected until the changes in Phys are merged or there is something else that needs updating

Changes to radiative lines leaked here but have been removed already.

Closes #192 (closed)

Updates to test output templates might be needed