message: Update to rand v0.4
diff: @@ -24,7 +24,7 @@ swizzle = []
  approx = "0.1"
  mint = { version = "0.4.1", optional = true }
  num-traits = "0.1"
  -rand = "0.3"
  +rand = "0.4"
  serde = { version = "1.0", features = ["serde_derive"], optional = true }
  simd = { version = "0.2", optional = true }
  