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, 4 insertions, 1 deletions

diff --git a/src/libtime/lib.rs b/src/libtime/lib.rs
index dfa9b924274..e58a0229d69 100644
--- a/src/libtime/lib.rs
+++ b/src/libtime/lib.rs
@@ -24,7 +24,9 @@
 
 #[cfg(test)] #[phase(plugin, link)] extern crate log;
 
+#[cfg(stage0)]
 extern crate serialize;
+extern crate "serialize" as rustc_serialize;
 extern crate libc;
 
 pub use self::ParseError::*;
@@ -76,7 +78,8 @@ mod imp {
 }
 
 /// A record specifying a time value in seconds and nanoseconds.
-#[deriving(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Show)]
+#[deriving(Clone, PartialEq, Eq, PartialOrd, Ord, RustcEncodable,
+           RustcDecodable, Show, Copy)]
 pub struct Timespec {
     pub sec: i64,
     pub nsec: i32,