Implement Base64 read.

src/bytes.rs

@@ -1,3 +1,4 @@
+#![allow(dead_code)]
 use std::fmt::Write; // need to import this trait
 
 #[derive(PartialEq, PartialOrd, Debug)]
@@ -34,7 +35,7 @@ impl Bytes {
         let Bytes(v) = self;
         let mut r = String::new();
         for e in v.iter() {
-            write!(r, "{:02x}", e);
+            write!(r, "{:02x}", e).unwrap();
         }
         r
     }