* xftp: cli client draft
* more stubs
* compiles
* hash, app
* options parsers, random
* tmp
* xftp CLI client agent, simplify CLI command syntax
* only allow argument as a second parameter
* pivot signature draft
* receive file
* pivot sent chunks to recipients
* encryptFile - temp, chunks, specs
* send (upload) file and save file descriptions
* refactor, remove encrypted file
* save file size in description as string
* include filename inside padded encrypted file
* call chunk uploads concurrently, using queueing in HTTP2 as library client does not support concurrent streaming uploads
* download file (does not work yet)
* add digests to sent chunks
* fix recv - save file using AppendMode
* encrypt/decrypt sent file with secretbox
* remove print
* fix file description parsing in tests
* fix test
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Co-authored-by: Evgeny Poberezkin <2769109+epoberezkin@users.noreply.github.com>
