fixup! parse block elements

src/main.rs

@@ -7,5 +7,6 @@ fn main() {
         .expect("failed to read utf-8 file");
 
     let p = jotdown::Parser::new(&src);
-    jotdown::html::write(std::io::stdout(), p).unwrap();
+    let mut out = std::io::BufWriter::new(std::io::stdout());
+    jotdown::html::write(&mut out, p).unwrap();
 }