These tests fail on the EN_US.UTF-8 locale.

Some fail due to a bug fixed in later AIX (lib/locale.t,
t/run/locale.t) and the other due to an apparent bug in the locale
itself.

https://perl5.test-smoke.org/report/5034327

Fix spelling on various files pertaining to core Perl.

This patch uses a collection of heuristics to skip test files which
would die on a perl compiled with -DNO_TAINT_SUPPORT but without
-DSILENT_NO_TAINT_SUPPORT.

-DNO_TAINT_SUPPORT disables taint support in a "safe" way, such that if
you try to use taint mode with the -t or -T options an exception will be
thrown informing you that the perl you are using does not support taint.
(The related setting -DSILENT_NO_TAINT_SUPPORT disables taint support
but causes the -t and -T options to be silently ignored.)

The error from using -t and -T is thrown very early in the process
startup and there is no way to "gracefully" handle it and convert it
into something else, for instance to skip a test file which contains it.

This patch generally fixes our code to skip these tests.

* Make t/TEST and t/harness check shebang lines and use filename checks
  to filter out tests that use -t or -T. Primarily this is the result of
  checking their shebang line, but some cpan/ files are excluded by
  name, either from a very short list of exclusions, or because their
  file name contains the word "taint". Non-cpan test files were fixed
  individually as noted below.

* test.pl - make run_multiple_progs() skip test cases based on the
  switches that are part of the test definition. This function is
  used in a great deal of our internal tests, so it fixes a lot of
  tests in one go.

* XS-APITest/t/call.t, t/run/switchDX.t, lib/B/Deparse.t - Skip a small
  set of tests in each file.

This adds 'taint_disabled' and 'taint_support' to Config.pm and %Config.
This way people can use them while we decide what to do about the
changes to Configure. We shouldn't need to have Configure changed to
export status variables like this in Config.pm

See: https://github.com/Perl-Toolchain-Gang/Test-Harness/pull/118
and: https://github.com/Perl/perl5/pull/20972

for related work that is stalled because we have not decided what
to do about these variables.

- fix (;$)
- remove infinite loops from check_proto()
- implement (+)
- fix (\@) and (\%)

Fixes GH #20989.

In particular, explain that "preserve permission bits like cp" means the
default behavior of /bin/cp, not "cp -p" or "cp --preserve", so the
umask still applies.

Previously it would default to Perl, which happens to produce the right
comment character ("#"), but results in nonsensical syntax highlighting.
Now we set $lang to the special value 'None', which still produces
read-only declarations, but doesn't force a mode/filetype on editors.

Vim's filetype declarations are case sensitive. The correct types for
Perl, C, and Pod are perl, c, and pod, respectively.

Module-CoreList was synced with CPAN and had its version in
Porting/Maintainers.pl updated. Module-CoreList was also updated
by running:

        ./perl -Ilib Porting/corelist.pl cpan

With some manual fixups afterwards to make it pass test.