Fix: modality refers to modality suffixes

[charlesbmi]

Thanks for this helpful library!

Looking at :
https://bids-specification.readthedocs.io/en/stable/appendices/entities.html#mod

it looks like mod- is only used for defacing masks, which might not be of interest to many. bids-examples only has 1 dataset that uses it.

BIDS seems to use modality to mostly refer to datatypes (already included in this API) or modality suffixes

[charlesbmi]

Actually, this is not quite right either:

from: https://bids.neuroimaging.io/standards/schema/schema-meta.html?h=modality#context

modality:       Modality of current file, for example, MRI

should this actually just backwards-look this up from the
https://bids.neuroimaging.io/getting_started/folders_and_files/folders.html#datatype ? i.e. datatype & supported-suffix specifies the modality?

[clane9]

Thanks for the PR and your interest in the library @charlesbmi! You are right, good catch. The mod entity has basically nothing to do with modality 😅. And indeed, the suffix seems to be the best way to get the modality.

I'm closing the PR though because the BIDSTable interface has been removed (at least for now) in bids2table 2.0 (#48). I feel like it is kind of unnecessary at this point, now that the table schema itself has been simplified to just the dataset, path, and BIDS entities. Although, please feel free to open a new issue if you think some BIDSTable-like convenience interface to the underlying table would be useful to have.