Document register_templates_directory being dependent on the dir_source feature
@@ -200,6 +200,9 @@ impl<'reg> Registry<'reg> {
/// will use their relative name as template name. For example, when `dir_path` is
/// `templates/` and `tpl_extension` is `.hbs`, the file
/// `templates/some/path/file.hbs` will be registerd as `some/path/file`.
+ ///
+ /// This method is not available by default.
+ /// You will need to enable the `dir_source` feature to use it.
#[cfg(feature = "dir_source")]
pub fn register_templates_directory<P>(
&mut self,
