Merge pull request containerd#79 from Tim-Zhang/upgrade-tokio

async: upgrade tokio to 1.0

Author: lifupan

Cargo.toml

@@ -20,9 +20,9 @@ byteorder = "1.3.2"
 thiserror = "1.0"
 
 async-trait = { version = "0.1.31", optional = true }
-tokio = { version = "0.2", features = ["rt-threaded", "sync", "uds", "stream", "macros", "io-util", "time"], optional = true }
+tokio = { version = "1", features = ["rt", "sync", "io-util", "macros", "time"], optional = true }
 futures = { version = "0.3", optional = true }
-tokio-vsock = { version = "0.2.1", optional = true }
+tokio-vsock = { version = "0.3", optional = true }
 
 [build-dependencies]
 protobuf-codegen-pure = "2.14.0"