• Allow integer and floating point type default to 0 when not provided
  without warning
  
• You can now take the sizeof a custom type (it will be the size of
  the native type that is actually passed on the C argument stack).
  
• Sizeof should be faster now as it doesn't look up the other meta
  information or create a hash to contain it
  
• Added record type see FFI::Platypus::Type#Records
  
• Added bool as a primitive type.