Declare MIT license in crate attributes, not BSD

The Rust License is actually the MIT license, not BSD

src/comp/rustc.rc

@@ -6,7 +6,7 @@
        url = "http://rust-lang.org/src/rustc")];
 
 #[desc = "The Rust compiler"];
-#[license = "BSD"];
+#[license = "MIT"];
 #[crate_type = "bin"];
 
 use std (name = "std",

src/libcore/core.rc

@@ -4,7 +4,7 @@
        url = "http://rust-lang.org/src/core")];
 
 #[comment = "The Rust core library"];
-#[license = "BSD"];
+#[license = "MIT"];
 #[crate_type = "lib"];
 
 export box, char, float, bessel, f32, f64, int, str, ptr;

src/libstd/std.rc

@@ -4,7 +4,7 @@
        url = "http://rust-lang.org/src/std")];
 
 #[comment = "The Rust standard library"];
-#[license = "BSD"];
+#[license = "MIT"];
 #[crate_type = "lib"];
 
 export comm, fs, io, net, run, uv;