import: accept more file paths

[clbarnes]

Given a lot of microscope output has very long names, I think a deep TIFF stack would quickly hit shell limitations on command length. Two ways round this:

1. Accept input from stdin
2. Accept a directory and discover files within it (sorting them) - probably better handled by piping fd | sort into option 1, but might be convenient for simple cases

Here's a repo which takes Vec<OsString>, where those OsStrings represent a mixture of file paths, directory paths, and - for stdin, and produces Vec<PathBuf> to files. Recursion into directories is optional and configurable.

https://github.com/clbarnes/filelist

[aschampion]

Good issue. One mitigation and otherwise complementary, useful feature would just be to have a block offset to import into a (potentially pre-existing) dataset, with manually specified total dimension. This would make it easier to distribute parallel imports and limit the number of files given to any one command.

Eventually I see import going away in its current form once ndgest succeeds n5gest, because image stacks will just be another chunknd-implementing backend which can be "imported" via convert, and it will be easy to specify arbitrary sources via stdin streaming or autodiscovery like you suggest.