rustc-ap-serialize 553.0.0

Automatically published version of the package `serialize` in the rust-lang/rust repository from commit 5aa3d9a7b5d3a46a7f158e8881146331a6bc9243 The publishing script for this crate lives at: https://github.com/alexcrichton/rustc-auto-publish

Support code for encoding and decoding types.