Bump rand_derive to 0.3.1
diff --git a/rand-derive/Cargo.toml b/rand-derive/Cargo.toml
index 593228b..c3edaff 100644
--- a/rand-derive/Cargo.toml
+++ b/rand-derive/Cargo.toml
@@ -1,7 +1,7 @@
 [package]
 
 name = "rand_derive"
-version = "0.3.0"
+version = "0.3.1"
 authors = ["The Rust Project Developers"]
 license = "MIT/Apache-2.0"
 readme = "README.md"