Re: [RFC] building postgres with meson -v8

More patches:

I fixed the Perl detection issue in my macOS environment that I had
reported a while ago.

Then I added in support for all configure options that had not been
ported over yet. Some of these are rather trivial.

After that, these configure options don't have an equivalent yet:

--disable-rpath
--enable-profiling
--disable-thread-safety
--with-libedit-preferred

The first three overlap with meson built-in functionality, so we would
need to check whether the desired functionality is available somehow.

The last one we probably want to keep somehow; it would need a bit of
fiddly work.