IMPLEMENTED composite evaluator and speed evaluator

DwaNavigator\DwaProblemOptimizer.cs: IDynamicWindowGenerator renamed to IVelocitySearchSpaceGenerator
DwaNavigator\DynamicDiamondGenerator.cs: contracts for IVelocitySearchSpaceGenerator implemented
IMPLEMENTED velocities evaluation, smoothing and optimization

REFACTORED velocity search space generation

DwaNavigator\DynamicDiamondGenerator.cs: returns 2-dimensional array of velocity-wheel acceleration pairs, which makes figuring out what wheel acceleration causes what velocity trivial
DwaNavigator\DwaProblemOptimizer.cs:  velocity evaluation matrix smoothing implemented
IMPLEMENTING integrating different DWA pieces into DwaNavigator