Update regexes.pod6

Note that wildcard C<.> now match "\n".
Rewrite comments in regexes to make it practical

Author: tisonkun

doc/Language/regexes.pod6

@@ -31,8 +31,9 @@ instead.
 Whitespace in regexes is generally ignored (except with the C<:s> or,
 completely, C<:sigspace> adverb).
 
-As with Perl 6, in general, comments in regexes start with a hash character
-C<#> and go to the end of the line.
+As with Perl 6, comments work as usual in regexes.
+
+    / word #`(match lexical "word") /
 
 =head1 Literals
 
@@ -84,6 +85,20 @@ This doesn't match:
 
 because there's no character to match before C<per> in the target string.
 
+Note that C<.> now does match B<any> single character, that is, it matches
+C<\n>. So the text below match:
+
+    my $text = qq:to/END/
+      Although I am a
+      multi-line text,
+      now can be matched
+      with /.*/.
+      END
+      ;
+
+    say $text ~~ / .* /;
+    # OUTPUT «｢Although I am a␤multi-line text,␤now can be matched␤with /.*/␤｣»
+
 =head2 Backslashed, predefined character classes
 
 There are predefined character classes of the form C<\w>. Its negation is