[BRLTTY] Making easier to accumulate filenames in theclipboard

[Sébastien Hinderer]

Hello Nicolas and many thanks for your proposed implementation, I think
it's indeed a very good idea!

I'm just unsure about the separator that shoudl  be used when
concatenating. I do understand that '\n' suits your use-case well, but,
after, all, why would ' ' (space) not be considered another legitimate
candidate?

Best wishes,

Sébastien.