Auto merge of #14889 - servo:rustup, r=jdm

Upgrade to rustc 1.16.0-nightly (6f1ae663e 2017-01-06)

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components/script/lib.rs

@@ -12,7 +12,6 @@
 #![feature(on_unimplemented)]
 #![feature(optin_builtin_traits)]
 #![feature(plugin)]
-#![feature(proc_macro)]
 #![feature(slice_patterns)]
 #![feature(stmt_expr_attributes)]
 #![feature(try_from)]