Rename error.type to kjType
Rename error.type to kjType

This a workaround due to a v8 bug:
https://code.google.com/p/v8/issues/detail?id=2397

martindale/node-capnp,kentonv/node-capnp,martindale/node-capnp,kentonv/node-capnp,martindale/node-capnp,martindale/node-capnp,kentonv/node-capnp