To simplify installation of polymake, we add some required CPAN packages.

Including recursive dependencies, these are 103 packages, a total of 7.5 MB of source archives, which we pack up as the source tar ball of the new spkg perl_cpan_polymake_prereq.
The source tar ball (attached) also contains a copy of the self-contained cpanm Perl script, which is used for installing the packages.
If SAGE_CHECK=no, only about 35 packages are installed. The rest of the dependencies are for testing.

Using an spkg-configure.m4, it is downloaded and installed only if the Perl packages are not already present on the system.

The spkg-install installs the packages via the package dependencies mechanism. If some of the packages are already installed in some version on the system, we do not install a newer version.

To try out:

   wget -P upstream https://github.com/sagemath/sage-prod/files/10659280/perl_cpan_polymake_prereq-2019-05-19.tar.gz

See also the sage-devel post about compilation: https://groups.google.com/forum/#!topic/sage-devel/ukJgMweHszU

Depends on #29582

CC: @dimpase @jplab lorenz@math.tu-berlin.de kastner@math.tu-berlin.de paffenholz@mathematik.tu-darmstadt.de

Component: packages: optional

Author: Matthias Koeppe

Branch/Commit: u/mkoeppe/perl_packages_for_polymake @ 225dea9

Issue created by migration from https://trac.sagemath.org/ticket/27763