Update `derivative` requirement from 1 to 2 (#140)

crypto-primitives/Cargo.toml

@@ -37,7 +37,7 @@ r1cs-std = { path = "../r1cs-std", optional = true, default-features = false }
 
 rand = { version = "0.7", default-features = false }
 rayon = { version = "1.0", optional = true }
-derivative = { version = "1.0", features = ["use_core"] }
+derivative = { version = "2.0", features = ["use_core"] }
 
 [features]
 default = ["std"]

r1cs-std/Cargo.toml

@@ -24,7 +24,7 @@ edition = "2018"
 [dependencies]
 algebra = { path = "../algebra", default-features = false }
 r1cs-core = { path = "../r1cs-core", default-features = false }
-derivative = { version = "1", features = ["use_core"] }
+derivative = { version = "2", features = ["use_core"] }
 
 [dev-dependencies]
 rand = { version = "0.7", default-features = false }