chore: remove tokio-futures facade crate (#1327)

This switches from using the tokio-futures facade to referencing
futures-* crates directly.

tokio/Cargo.toml

@@ -40,7 +40,7 @@ default = [
 
 codec = ["io", "tokio-codec"]
 fs = ["tokio-fs"]
-io = ["bytes", "tokio-io", "tokio-futures", "memchr"]
+io = ["bytes", "tokio-io", "memchr"]
 reactor = ["io", "tokio-reactor"]
 rt-full = [
   "num_cpus",
@@ -82,9 +82,6 @@ tokio-timer = { version = "0.3.0", optional = true, path = "../tokio-timer" }
 tracing-core = { version = "0.1", optional = true }
 memchr = { version = "2.2", optional = true }
 
-# Needed for async/await preview support
-tokio-futures = { version = "0.2.0", optional = true, path = "../tokio-futures" }
-
 [target.'cfg(unix)'.dependencies]
 tokio-uds = { version = "0.3.0", optional = true, path = "../tokio-uds" }
 

tokio/src/io/lines.rs

@@ -1,11 +1,12 @@
 use super::read_line::read_line_internal;
-use futures_core::ready;
+
+use tokio_io::AsyncBufRead;
+
+use futures_core::{ready, Stream};
 use std::io;
 use std::mem;
 use std::pin::Pin;
 use std::task::{Context, Poll};
-use tokio_futures::Stream;
-use tokio_io::AsyncBufRead;
 
 /// Stream for the [`lines`](crate::io::AsyncBufReadExt::lines) method.
 #[derive(Debug)]