Splits stdin of unknown size onto chunks of given size and collects such chunk
files as a TAR archive what is written to stdout.

Initial motivation was to use it as a packer of a data stream what pipes it to
https://tarsnap.com for backup purposes, with a requirement of low and more
predictable memory consumption. And the problem solved here is that TAR file
header should specify size of a file, but it's unknown due to the nature of
input data stream.

The following real case could be an example:
$ pg_dump ... | tar_stream_chunker ... | tarsnap -c ... @-