Added todo

src/main.rs

@@ -5,6 +5,8 @@ use anyhow::{Context, anyhow};
 use clap::Parser;
 use huffman::{cli, hufftree, storage};
 
+// TODO: Add STDIN as input
+
 fn main() -> Result<(), anyhow::Error> {
     let args = cli::Args::parse();