Convert most code to new inner attribute syntax.

Closes #2569

src/test/compile-fail/lint-uppercase-variables.rs

@@ -8,7 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#[deny(uppercase_variables)];
+#![deny(uppercase_variables)]
 
 use std::io::File;
 use std::io::IoError;