base for collision models for fluid particle interaction

Parameters:

collision_model (type: string) name of the collision model
detection_method (type: string) method to detect collisions
collision_duration (type: float) duration of the collision in seconds;
activate_collision_before_impact (type: int) activate collision before impact (1) or not (0)
activation_distance_percentage_diameter (type: float) activation distance of the collision process as a percentage of the particle diameter
force_on_two_phase_elem (type: int) force on two phase elements (1) or not (0). Only valid for a single particle.