Remove SDB support?

[JRMeyer]

Looking through the augmentation docs today, I saw reference to .sdb files and thought we had already removed support for the Sample Database file format

I now see that's not the case, and we still have code for use of sdb files. However, as far as I know no one is using this custom file format, and given that we are moving to more modern data input methods (e.g. streaming of webdatasets), the sdb file format feels like a legacy approach we could remove to keep the code and docs leaner.

thoughts?

[reuben]

We'll take silence as evidence of no use :)