default_features is deprecated - switch it to default-features

Author: LikeLakers2

Cargo.toml

@@ -30,7 +30,7 @@ rand = "0.7"
 criterion = { version = "0.4.0", features = ["html_reports"] }
 paste = "1.0.0"  # Used in test_std to instantiate generic tests
 permutohedron = "0.2"
-quickcheck = { version = "0.9", default_features = false }
+quickcheck = { version = "0.9", default-features = false }
 
 [features]
 default = ["use_std"]