The new ghostscript could not decrypt some password protected files. It turned out to be a bug in ghostscript but in the process of investigating I thought it might be related to missing libidn that is also used in PDF passwords, so I added it.

See merge request nexedi/slapos!1455

Fixes decryption of some password protected PDFs

INFO configure: WARNING: unrecognized options: --disable-threadsafe

without libidn, decrypting password protected PDFs does not fully work.

This is a fixup of f6281e7a.

This fixes 3c514224

Since nginx 1.25.1 ssl directive has been dropped, so fix the configuration
template to work with 1.25.2.

Update nginx-push-stream to follow nginx API changes.

Will support zlib 1.3+

Extend PATH to make xzcat available.

Extend PATH to make xzcat available.

Enforce python3 usage, as the newer version requires python3.