Merge pull request #7 from taiki-e/dependencies

Update dependencies

Author: yoshuawuyts

Cargo.toml

@@ -13,9 +13,9 @@ categories = ["asynchronous", "concurrency"]
 readme = "README.md"
 
 [dependencies]
-crossbeam-utils = "0.6.5"
+crossbeam-utils = "0.7.0"
 
 [dev-dependencies]
-crossbeam = "0.7.1"
-futures-preview = "0.3.0-alpha.17"
-lazy_static = "1.3.0"
+crossbeam = "0.7.3"
+futures = "0.3.1"
+lazy_static = "1.4.0"