Add license.

Author: bsansouci

opam

@@ -1,5 +1,6 @@
 opam-version: "1.2"
 version: "0.0.1"
+license: "BSD"
 dev-repo: "https://github.com/reasonml/ReasonNativeProject.git"
 maintainer: "FirstName LastName <email@email.com>"
 authors: [ "FirstName LastName <email@email.com>" ]

package.json

@@ -17,5 +17,6 @@
     "dependencies": {
       "reason": "build & >=  \"1.13.3\""
     }
-  }
+  },
+  "license": "BSD"
 }