Writes a gzipped _physio.tsv.gz (headerless, columns defined in the
JSON) plus a _physio.json sidecar with SamplingFrequency,
StartTime and Columns.
Usage
writeBIDSPhysio(
x,
bids_root,
subject,
task,
session = NULL,
run = NULL,
start_time = 0,
overwrite = FALSE
)