Fix unity-native-plugin-sys/Cargo.toml

Author: aosoft

unity-native-plugin-sys/Cargo.toml

@@ -3,6 +3,8 @@ name = "unity-native-plugin-sys"
 version = "0.1.0"
 authors = ["Yasuhiro Taniuchi"]
 edition = "2018"
+license = "MIT"
+description = "unity-native-plugin-sys"
 homepage = "https://github.com/aosoft/unity-native-plugin-rs"
 repository = "https://github.com/aosoft/unity-native-plugin-rs"
 readme = "README.md"