Update sphere.py -- add pooling and max_pooling

[mzameshina]

Types of changes

• Docs change / refactoring / dependency upgrade
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Motivation and Context / Related issue

How Has This Been Tested (if it applies)

Checklist

• The documentation is up-to-date with the changes I made.
• I have read the CONTRIBUTING document and completed the CLA (see CLA).
• All tests passed, and additional code has been covered with new tests.

[teytaud]

Please use the same signature as other codes so that it can work in the quasi-randomize function.

Please add your code as default in quasi-randomize, when len(shape) > 1, instead of dispersion_with_big_conv.

[teytaud]

All methods in the list have the same signature, so that they can be used by quasi-randomize.
Please use the same signature.

[teytaud]

Does it run ? This does not work as Torch is not in the dependencies.
I recommend not using torch, as it would imply a big dependency.

Also you need black.