Change SUPG OPTION from a 4 integer array to 1 single integer

As only the 1st component of the 4 integer array OPTSUP (MNEMO for keyword SUPG OPTION) is read and used in TELEMAC-3D, the keyword can be changed to 1 single integer as discussed during SciCo 2024, see #991 The same choice is applied to U, V and W, but also to tracer(s), k and epsilon if needed. If using SUPG for advection of tracers and willing the classigal SUPG = 1', it then be less confusing to set e.g. 1 rather than 1;0;1;0 worse 1;0;2;0 as only the 1st component was read and used.