patch to update nodejs to 10.20.1

[Gábor Csárdi]

Hi all,

this is not the most recent version, not even the most recent LTS, but
still officially supported for about a year
(https://nodejs.org/en/about/releases/) I'll try to build the newer
versions as well.

Some notes and glitches:
- the original tarball has two files with dollar signs in the name,
which is not allowed in a pkg, so we rename then before packaging, and
rename them again in postinstall.
- I had to use the built-in openssl, libcares and zlib libraries
instead of using the opencsw ones, because the first two are old, and
the third does no work properly.

Lightly tested, seems to work pretty well.

Hopefully you can add this to unstable.

Cheers,
Gabor