serialize: Fully deprecate the library

This commit completes the deprecation story for the in-tree serialization
library. The compiler will now emit a warning whenever it encounters
`deriving(Encodable)` or `deriving(Decodable)`, and the library itself is now
marked `#[unstable]` for when feature staging is enabled.

All users of serialization can migrate to the `rustc-serialize` crate on
crates.io which provides the exact same interface as the libserialize library
in-tree. The new deriving modes are named `RustcEncodable` and `RustcDecodable`
and require `extern crate "rustc-serialize" as rustc_serialize` at the crate
root in order to expand correctly.

To migrate all crates, add the following to your `Cargo.toml`:

    [dependencies]
    rustc-serialize = "0.1.1"

And then add the following to your crate root:

    extern crate "rustc-serialize" as rustc_serialize;

Finally, rename `Encodable` and `Decodable` deriving modes to `RustcEncodable`
and `RustcDecodable`.

[breaking-change]

1 files changed, 1 insertions, 1 deletions

diff --git a/src/libsyntax/abi.rs b/src/libsyntax/abi.rs
index 70bad90aea1..b1599cb807d 100644
--- a/src/libsyntax/abi.rs
+++ b/src/libsyntax/abi.rs
@@ -26,7 +26,7 @@ pub enum Os {
     OsDragonfly,
 }
 
-#[deriving(Copy, PartialEq, Eq, Hash, Encodable, Decodable, Clone)]
+#[deriving(PartialEq, Eq, Hash, RustcEncodable, RustcDecodable, Clone, Copy)]
 pub enum Abi {
     // NB: This ordering MUST match the AbiDatas array below.
     // (This is ensured by the test indices_are_correct().)