Rename macro_escape to macro_use

In the future we want to support

    #[macro_use(foo, bar)]
    mod macros;

but it's not an essential part of macro reform.  Reserve the syntax for now.

src/libcoretest/num/mod.rs

@@ -14,7 +14,8 @@ use core::num::{NumCast, cast};
 use core::ops::{Add, Sub, Mul, Div, Rem};
 use core::kinds::Copy;
 
-#[macro_escape]
+#[cfg_attr(stage0, macro_escape)]
+#[cfg_attr(not(stage0), macro_use)]
 mod int_macros;
 
 mod i8;
@@ -23,7 +24,8 @@ mod i32;
 mod i64;
 mod int;
 
-#[macro_escape]
+#[cfg_attr(stage0, macro_escape)]
+#[cfg_attr(not(stage0), macro_use)]
 mod uint_macros;
 
 mod u8;