Add path modification methods

[adelavega]

• build_path
• write_to_file
• copy_file

[erdalkaraca]

Seems like these methods are meant to allow creating derivatives? ancpbids has support for creating in-memory structure of a derivative (folders/files), then saving that structure to file system.

[adelavega]

I'm not familiar w/ all of these functions, but yes generally speaking. They are just simple helper functions

[effigies]

They are not necessarily for creating derivatives. They are also there to generate valid raw dataset paths, for instance for tools that are used to curate BIDS datasets in the first place.