Since all our python scripts have a proper python3 shebang, there is no benefit
to letting meson autodetect them. On linux, meson will just uses exec(), so the
shebang is used anyway. The only difference should be in how meson reports the
script and that the detection won't fail for (most likely misconfigured)
non-UTF8 locales.
Closes#5855.
This is useful on systems like NixOS, where python3 is not in
/usr/bin/python3 as well as for people using alternative ways to
install python such as virtualenv/pyenv.
The idea is that after adding a new man page, make update-man-list
will be used to regenerate part of the makefile. So the data already
present in the makefile cannot be used to do that.
Also, renames filter out generated xml files in make-man-rules.py
itself in order to make Makefile.am a bit simpler, and rename files
to dist_files to better reflect new meaning.