Spriteworld Versions Save

Several changes and bugfixes, which may need you to update your scripts:

1. Shapes are now rotated to have a canonical orientation which corresponds to the COBRA paper. E.g. "square" was rotated as a diamond, it is now axis-aligned.
2. Modified Rendering orientation. Everything is now using (bottom-left) as the (0, 0) origin, even the pixel rendering. This makes everything self-consistent (actions, sprite positions, renders and transformations), but might require you to remove transposes/origin='lower' from your code.
3. There was too much default action noise injected in the COBRA configs, which meant that clicking on an object would be ~impossible for an agent. This has been reverted.

To reproduce COBRA results while training a transition model, consider adding some noise in the velocity components only, see Appendix for details.

Initial stable release.