message: Add namespaced-features option for manifest [project] section
diff: @@ -543,6 +543,8 @@ pub struct TomlProject {
  autoexamples: Option<bool>,
  autotests: Option<bool>,
  autobenches: Option<bool>,
  + #[serde(rename = "namespaced-features")]
  + namespaced_features: Option<bool>,
  // package metadata
  description: Option<String>,
  