[Perl/perl5] 191512: [doc] update description of $^H and %^H inperlvar

  Branch: refs/heads/blead
  Home:   https://github.com/Perl/perl5
  Commit: 19151286d6e3fc6fd8238e85d78ea74f2cae3cc8
      https://github.com/Perl/perl5/commit/19151286d6e3fc6fd8238e85d78ea74f2cae3cc8
  Author: Lukas Mai <lukasmai.403@gmail.com>
  Date:   2023-03-28 (Tue, 28 Mar 2023)

  Changed paths:
    M pod/perlvar.pod

  Log Message:
  -----------
  [doc] update description of $^H and %^H in perlvar

- remove trailing spaces
- add hyperlink to "caller" in perlfunc
- add hyperlink to $^H in description of %^H
- change "pointers to objects" to "references to objects"
- change "semantic" to "semantics"
- reword "useful for implementation of pragmas" as "useful for
  implementing pragmas"

• [Perl/perl5] 191512: [doc] update description of $^H and %^H inperlvar by mauke via perl5-changes