Simple project to understand how Godot acceleration works in KinematicBodies

@author Rafael G. de Pontes

Notes:

• Distance is measured in pixels
• Time is in seconds

There are 3 bodies, with initial velocity = 1 pixel/second towards the right (+x axis):

1. Constant velocity of 1 pixel/second
2. Increased by 1.0 pixel/physics_frame (every _physics_process call)
3. Increased by 1.0 * delta pixel/physics_frame (every _physics_process call)

Conclusion: if you want to properly accelerate a KinematicBody2D, you have to multiply acceleration by delta every _physics_process call before adding to the KB2D velocity.