Unexpected behavior importing nested modules with the same name

The following test results in items in the inner foo not being resolved even though the compiler let us import foo::foo

```
import foo::foo;

mod foo {  
  mod foo {
    fn baz() {
    }
  }
}

fn main() {
  // error: unresolved name: baz                                                                         
  foo::baz();
}
```

Also, using `import foo = foo::foo` has the same result.
