Vendor dependencies

Let's see how I like this workflow.

vendor/bytes/tests/test_reader.rs

@@ -0,0 +1,29 @@
+#![warn(rust_2018_idioms)]
+#![cfg(feature = "std")]
+
+use std::io::{BufRead, Read};
+
+use bytes::Buf;
+
+#[test]
+fn read() {
+    let buf1 = &b"hello "[..];
+    let buf2 = &b"world"[..];
+    let buf = Buf::chain(buf1, buf2); // Disambiguate with Read::chain
+    let mut buffer = Vec::new();
+    buf.reader().read_to_end(&mut buffer).unwrap();
+    assert_eq!(b"hello world", &buffer[..]);
+}
+
+#[test]
+fn buf_read() {
+    let buf1 = &b"hell"[..];
+    let buf2 = &b"o\nworld"[..];
+    let mut reader = Buf::chain(buf1, buf2).reader();
+    let mut line = String::new();
+    reader.read_line(&mut line).unwrap();
+    assert_eq!("hello\n", &line);
+    line.clear();
+    reader.read_line(&mut line).unwrap();
+    assert_eq!("world", &line);
+}