• Updated non-binding support for Perls to match the policy
  of the Perl toolchain (Perls older than 10 years old are
  unsupported, with a one-time exception of Perl 5.16). The
  intent is not to suddenly drop support for older Perls, but
  the FFI-Platypus team may take advantage of features in
  supported Perls that will effectively remove compatability
  with unsupported Perls.
  
• Documentation improvements (gh#392)