public interface ODEAdaptiveSolver
ODEAdaptiveSolver extends the ODE solver to add adaptive step size capabilities.
Adaptive ODE solvers adjust the step size until that the desired tolerance is reached.
The client's state can effect the internal state of the ODE solver. Some adaptive solvers
advance an internal copy of client's state. This internal state is then copied to the client after
every step. Other solvers estimate the optimal time step using the client's state. Clients
should therfore always invoke the solver's initialize method after setting their initial conditions.