perl5420delta: Add detail to perlop changes

Author: khwilliamson

pod/perldelta.pod

@@ -573,6 +573,32 @@ Additional caveats have been added to the description of C<TARG>.
 
 =item *
 
+Portions of perlop are supposed to be ordered so that all the operators
+wth the same precedence are in a single section, and the sections are
+ordered so that the highest precedence operators appear first.
+This ordering has now been restored.  Other reorganization was done to
+improve clarity, with more basic operations described before ones that
+depend on them.
+
+=item *
+
+The documentation for here-docs has been cleaned up and reorganized.
+Indented here-docs were formerly documented separately, now the two
+types have interwoven documentation which is more compact, and easier to
+understand.
+
+=item *
+
+The documentation of the C<xor> operator has been expanded.
+
+=item *
+
+Outdated advice about using relational string operators in UTF-8 locales
+has been removed.  Use L<Unicode::Collate> for the best results, but
+these operators will give adequate results on many platforms.
+
+=item *
+
 Normalized alignment of verbatim sections, fixing how they are displayed by
 some Pod viewers that strip indentation.