tools/amalgamate/README.md is the unmodified upstream text and no
longer matches how the tool is used here:
- It named a Bitbucket origin that no longer exists; CHANGES.md
already tracks the GitHub mirror commit this copy is based on.
- It asked for Python 2.7, but CI and the Makefile run the script
with python3.
- It told readers to run ./test.sh (not vendored) and install to
/usr/local/bin; in this repository the tool runs through
`make amalgamate`.
- Its usage synopsis showed `-v` taking no argument, but the script's
own argparser requires `choices=["yes", "no"]`, so that form fails
with "argument -v/--verbose: expected one argument". The Makefile
calls it as `--verbose=yes`.
- It pointed at test/source.c.json and test/include.h.json, which are
not vendored; the configs actually used are config_json.json and
config_json_fwd.json.
Rewrote only the Installing and Using sections to match; left the
"Here be dragons" caveats and the rest of the vendored code untouched
to avoid diverging further from upstream.
Overlaps #5615, which edits amalgamate.py, this README and CHANGES.md.
#5717 item 6
Signed-off-by: Niels Lohmann <mail@nlohmann.me>