Copy over missing doc comments
diff --git a/src/attr.rs b/src/attr.rs
index e08d9c7..10c8029 100644
--- a/src/attr.rs
+++ b/src/attr.rs
@@ -1,5 +1,6 @@
 use super::*;
 
+/// Doc-comments are promoted to attributes that have is_sugared_doc = true
 #[derive(Debug, Clone, Eq, PartialEq)]
 pub struct Attribute {
     pub value: MetaItem,