feat(http): use the bytes crate for Chunk and internally

src/http/body.rs

@@ -1,9 +1,9 @@
-use std::convert::From;
-
-use tokio_proto;
-use http::Chunk;
+use bytes::Bytes;
 use futures::{Poll, Stream};
 use futures::sync::mpsc;
+use tokio_proto;
+
+use http::Chunk;
 
 pub type TokioBody = tokio_proto::streaming::Body<Chunk, ::Error>;
 
@@ -58,6 +58,12 @@ impl From<Chunk> for Body {
     }
 }
 
+impl From<Bytes> for Body {
+    fn from (bytes: Bytes) -> Body {
+        Body(TokioBody::from(Chunk::from(bytes)))
+    }
+}
+
 impl From<Vec<u8>> for Body {
     fn from (vec: Vec<u8>) -> Body {
         Body(TokioBody::from(Chunk::from(vec)))