Add UR5e and UR20 models

[javijurado]

Since I used your library for my project and I had to add two new UR robots, I decided to create this PR for others to use.

The UR5e and UR20 have been added. The data has been extracted from here: link

[javijurado]

@petercorke Who can review this PR?

[floxdeveloper]

For me the collision checking is not working for your UR5e model.
I copied your UR5e to a folder models and created an __init__.py for it and ran the following code:

from models import UR5e
from spatialgeometry import Sphere
from spatialmath import SE3
import roboticstoolbox


def main():
    # Position of the laser tracker (in meters, relative to the robot base frame)
    LASER_TRACKER_POSITION = [0.0, 0.005, 0.008]  # [x, y, z] in meters
    LASER_TRACKER_RADIUS = 0.0005   # 1 mm diameter

    # Load UR5e robot
    ur5e = UR5e()
    print("UR5e model loaded:")
    print(ur5e)

    # Create laser tracker as a sphere
    tracker_pose = SE3(*LASER_TRACKER_POSITION)
    laser_tracker = Sphere(
        radius=LASER_TRACKER_RADIUS,
        pose=tracker_pose,
        collision=True,
        color=[1, 0, 0, 1]  # Red, fully opaque
    )
    print("Laser tracker (sphere) placed at:", LASER_TRACKER_POSITION)
    print(laser_tracker)

    ur5 = roboticstoolbox.models.UR5()
    obstacle = laser_tracker
    print(ur5.iscollided(ur5.qr, obstacle))

    print(ur5e.iscollided(ur5e.qr, obstacle))

    d, p1, p2 = ur5e.closest_point(ur5e.qr, laser_tracker)
    print(d, p1, p2)

if __name__ == "__main__":
    main()

I receive True for the UR5, but False for your UR5e model.

Could you please check it again?