Recipes for Perl modules are simple.
These recipes usually only need to point to the source's archive and then inherit the
proper .bbclass file.
Building is split into two methods depending on which method the module authors used.
Modules that use old Makefile.PL-based build system require
cpan.bbclass in their recipes.
Modules that use Build.PL-based build system require
using cpan_build.bbclass in their recipes.