Query for transforms without downloading #142
Description
I am thinking of NiPost workflows where we may have an input dataset with data in a particular space, and want to apply transforms to get the data into a different space, but we don't have a predefined list of transforms between those spaces. It would be great to use templateflow.api.get to get a list of all of the available transforms from TemplateFlow without downloading them. Then, the NiPost workflow could select the transforms that make the shortest path from the input space to the target space (see nipreps/fmripost-aroma#24) and download only those transforms that it needs.