perl 5.8.8: Improvements for cpan modules:

perl 5.8.8: Improvements for cpan modules:
* Modify perl to install a copy of it's configuration during staging. This
  will allow us to get at the perl settings for the target when building
  cpan modules.
* Modify perl-native to allow selection of the host or target configuration
  based on an environment variable. This will allow the cpan class to select
  the appropriate configuration based on if we are building the native
  package or not.
* Modify cpan.bbclass to set the environment variable to an appropriate
  value to tell perl native to select the appropriate settings based on if
  we are building native or target modules.
This change fixes some modules that were compiled for the host instead of
the target (libversion-perl for example) and fixes up some of cpan modules
that include additional subdirectories with their own makefiles.