use [repr(u8)] for FieldSize and WirePointerKind
use [repr(u8)] for FieldSize and WirePointerKind

placrosse/capnproto-rust,dwrensha/capnproto-rust,danburkert/capnproto-rust,maurer/capnproto-rust,larquin/capnproto-rust,tempbottle/capnproto-rust