Perl pragma for deprecating the inclusion of a module in core
Description
"deprecate" pragma simplifies the maintenance of dual-life modules that will no
longer be included in the Perl core in a future Perl release, but are
still included currently. The purpose of the pragma is to alert users to the
status of such a module by issuing a warning that encourages them to install
the module from CPAN, so that a future upgrade to a perl which omits the
module will not break their code.