DUNE/Plans: SpeedConversion is now called SpeedModel and works as an object rather than some static functions. Speed models are now mmember variables.
DUNE/Plans: Adapted TimeProfile to changes in SpeedModel.
DUNE/Plans: PowerModel now receives pointer to config in constructor. Made some functions const.
Plan/Engine: Adapted FuelPrediction to changes in speed and power models. Pointer to power model is now const.
Plan/Engine: Power and speed models are now initialised in Plan's constructor. Models are validated.