stanley controller: get all vehicle related parameters from vehicle_info
Currently only wheel_base length is from platform_params.yaml. Other vehicle parameters should be also retrieved from there during launch. These params are listed as the following:
- front left mass: mass_fl
- front right mass: mass_fr
- rear left mass: mass_rl
- rear right mass: mass_rr
- front tire cornering stiffness: cf
- rear tire cornering stiffness: cr