Still using `partial_fill` when creating FileTreeQuery

Added test for I/O to both JSON and pickle files

Also added test for add_to_parser

env option

double-barrelled filename support (but not HCP files :( )

This is now the new default behaviour when loading a new file

This change is not backwards compatible!

There were some subtle bugs in the use of get_all, which should now be fixed. They were caused by having multiple optional variables and the result not being deterministic if these were iterated in different orders.

affine.rescale function, for reuse.

directory check to be skipped

auto-load any JSON files that sre found. Fix to bids.isBIDSFile

flag.

synchronously

module-level functions. No changes to functionality

it blocks for