• Catalyst was relying on the internals of the old slurpy function. Next
  release of Catalyst should fix that, but this version of Types::Standard
  introduces a workaround for the issue without going back to implementing
  Slurpy the old way. (The Catalyst test suite passes at least!)
  
• In most places that accept a Slurpy, happily accept a child of a child
  of a child of Slurpy.
  
• Rename Type::Params::Coderef to Eval::TypeTiny::CodeAccumulator as it's
  not really Type::Params-specific. Add test cases for it and make it part
  of the public API.
  
• Use Eval::TypeTiny::CodeAccumulator in compile_match_on_type.
  
• When Type::Tiny's is_subtype_of, etc methods are called passing a string
  as a parameter, pay attention to calling package's type registry.