some fixes

[milahu]

mostly avoid creating tempfiles

tested briefly

[fentas]

Juhu, why rename the main file? 👀

[milahu]

mv bin/tus bin/tus-client.sh
because file extension → syntax highlighting
because tus is the protocol, and this is a client

[fentas]

This would be a breaking change, and this script behaves more like a binary or executable than a script.
Most editors recognise the shebang but if needed, we can also add these:

# shellcheck shell=bash
# vim: set syntax=bash:

[milahu]

ok, reverted to bin/tus