Spec clean-up
    
    - License is "GPLv2 or Artistic", not "GPLv2+ or Artistic"
    - BR: perl(Test::Pod) for additional test coverage
    - BR: Perl core modules that might be dual-lived
    - Make %files list more explicit
    - Drop %defattr, redundant since rpm 4.4
    - Fix provides filter to work with rpm ≥ 4.9
    - Don't need to remove empty directories from buildroot
    - Use DESTDIR rather than PERL_INSTALL_ROOT
    - Don't use macros for commands
    - Reinstate buildroot definition and cleaning for EPEL-5 compatibility
    - Use tabs