Merge branch 'blead' of ssh://perl5.git.perl.org/gitroot/perl into blead

Merge branch 'blead' of ssh://perl5.git.perl.org/gitroot/perl into blead

* 'blead' of ssh://perl5.git.perl.org/gitroot/perl:
  Warn people not to set PERL_CORE in XS
  In embed.fnc the 'E' flag should imply 'X', but doesn't.
  revise perldelta note on strict and lax version rules
  expand flag descriptions in in embed.fnc
  alphabetically sort flag descriptions in embed.fnc
  [perl #72156]: substitute `less -R' for `less' for groff's new usage
  INSTALL doc fix: calling the test suite using -MTestInit changed since it moved to top level (which happened in commit 30b6e59101b252c20a6b50b95203d1e2c6016604)
  changed "an UTF..." to "a UTF..." in all Pods