Update notebooks to use GCS FUSE

[cxgoogle]

Saves having to download DICOM/embeddings files to the Colab instance. Keeps the content more focused and saves the user time.

Also, it removes the need for the semi-confusing labels DF dual columns, with the remote file path and the local downloaded file path.

Note: this would work well for Colab and Linux, but FUSE is not supported on Windows/Mac, for users who would want to run it locally.