ENH: Implement BIDS filters file and drop legacy BIDS querying

[oesteban]

Requires: nipreps/niworkflows#833.

Resolves: #760 .

[Remi-Gau]

@oesteban
random question: quick look at the code makes me think this only works at the individual level, no?
if one wanted to use the bids filter to make group summary plot of only a subset of images, this filtering would not work, right?

[oesteban]

quick look at the code makes me think this only works at the individual level, no?

Correct

if one wanted to use the bids filter to make group summary plot of only a subset of images, this filtering would not work, right?

This would be a good idea, but as you expect, it will not work ATM. However, it is definitely a good idea for any takers.