Broken on 1.11.0-nightly (5522e678b 2016-06-20)

[dtolnay]

Due to the removal of GatedCfgAttr in rust-lang/rust#34272.

   Compiling aster v0.18.0
error: unresolved import `syntax::feature_gate::GatedCfgAttr`. There is no `GatedCfgAttr` in `syntax::feature_gate`. Did you mean to use `GatedCfg`? [--explain E0432]
 --> src/mac.rs:6:5
  |>
6 |> use syntax::feature_gate::GatedCfgAttr;
  |>     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: this function takes 4 parameters but 5 parameters were supplied [--explain E0061]
   --> src/mac.rs:113:18
    |>
113 |>     let mut cx = ExtCtxt::new(sess, cfg, ecfg, feature_gated_cfgs, macro_loader);
    |>                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
note: the following parameter types were expected: &syntax::parse::ParseSess, std::vec::Vec<syntax::ptr::P<syntax::codemap::Spanned<syntax::ast::MetaItemKind>>>, syntax::ext::expand::ExpansionConfig<'_>, &mut syntax::ext::base::MacroLoader

error: aborting due to previous error
error: Could not compile `aster`.

For some reason the nightli.es build 11 hours ago ran with rustc 1.11.0-nightly (bb4a79b08 2016-06-15)... possibly related to serde-deprecated/syntex#76 (comment).