Update GNN notebook (#167)

This PR updates the GNN notebook since some commands are not working for
the lastest version of torch_geometric as discussed in issue
#166.

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Fixing 404 errors of links to notebooks in the documentation (#143)

I assume that the notebooks have been moved, but the documentation links
did not reflect that

**Legal Acknowledgement**\
By contributing to this software project, I agree my contributions are
submitted under the BSD license.
I represent I am authorized to make the contributions and grant the
license.
If my employer has rights to intellectual property that includes these
contributions,
I represent that I have received permission to make contributions and
grant the required license on behalf of that employer.

Merge pull request #99 from cog-imperial/coin-or-badge

Add coin-or cup badge

Merge pull request #51 from cog-imperial/add-cnn-tests

Test ConvLayer

Merge pull request #51 from cog-imperial/add-cnn-tests

Test ConvLayer

Update package metadata

Update package metadata

remove raw directive in readme