Solver interface consistency with warmstart=True/False

[qtothec]

Do we enforce/is there in practice consistency with respecting the warmstart=True or warmstart=False solve options among all the solver interfaces?

This is motivated by the following SO question: https://stackoverflow.com/questions/49288060/initialize-and-warmstart-parameters-on-pyomo

[Iakl]

As for now, if i use warmstart argument with Ipopt solver, Pyomo raises a ValueError saying that "warmstart" key is not defined.