Revert "fix Peek.t to work with NEW COW"

This reverts commit 2b656fcc48f28912136698c28b3bd916c42d74f8.

I accidentally included the changes I was reviewing from a patch of
Reini's
fix Peek.t to work with NEW COW
Add epigraph for 5.17.10
improve iterator randomization
Add a commented out warning and a way for diag.t to ignore it
improve how Devel::Peek::Dump handles iterator information

* If the hash is not OOK omit any iterator status information
  instead of showing -1/NULL
* If the hash is OOK then add the RAND value from the iterator
  and if the LASTRAND is not the same show it too
* Tweak tests to test the above.
Revert "Restore errno after VMS hack in S_sv_gets_read_record."

This reverts commit d46f021e36854e800770363f716e7b4a846102ef.

This can be done more universally (and from the point of view of
sv.c, less obtrusively) in Perl_flex_fstat in vms/vms.c.
Make vms.c's Perl_flex_fstat preserve errno on success.

The CRTL's fstat() sets errno to EVMSERR and vaxc$errno to RMS$_IOP
when called on a proccess-permanent file (i.e., stdin, stdout, or
stderr).  That error generally means a rewind operation on a file
that cannot be rewound.  It's odd that fstat is doing such a thing,
but we can at least protect ourselves from the effects of it by
saving errno and restoring it on a successful call.

This cures a couple of test failures and TODOs in t/io/errno.t.
Copyright update for vms/vms.c.

Happy 20th Anniversary, Charles.
File::Glob: Drop dependency on given/when
Porting/checkpodencoding.pl: Drop dependency on smartmatch
Porting/core-cpan-diff: Drop dependency on smartmatch
t/re/regexp_unicode_prop.t: Drop dependency on given/when
t/porting/dual-life.t: Drop dependency on smartmatch
Make smartmatch, given & when experimental
Silence "smartmatch is experimental" warnings in autodie