[Refactor] Refactor camera frame creation APIs

[yxlao]

This is an API-breaking change.

Summary

# Create camera frame with Ks, Ts.
ct.camera.create_camera_frames(Ks=Ks, Ts=Ts)

# Create camera frames with Ts only.
ct.camera.create_camera_frames_with_Ts(Ts)  # Equivlaent to below
ct.camera.create_camera_frames(Ks=None, Ts=Ts)

# Create camera frames without up_triangle.
ct.camera.create_camera_frames(up_triangle=False)

# Create camera frames with center ray.
ct.camera.create_camera_frames(center_ray = True)

Changes

• Rename ct.camera.create_camera_ray_frames() to ct.camera.create_camera_frames().
• Remove ct.camera.create_camera_center_ray() and ct.camera.create_camera_center_rays()
  • This can be controlled by the center_ray parameter in ct.camera.create_camera_frames.