attempt to fix jspm

Author: make-github-pseudonymous-again

config.js

@@ -1,4 +1,9 @@
 System.config({
+  packages: {
+    'lib/**': {
+      main: 'index.js',
+    }
+  },
   baseURL: "/",
   defaultJSExtensions: true,
   transpiler: "babel",

package.json

@@ -19,7 +19,8 @@
     "url": "https://github.com/aureooms/es-red-black-tree/issues"
   },
   "scripts": {
-    "preversion": "babel src -d lib",
+    "build": "babel src -d lib",
+    "prepublish": "npm run build",
     "test": "ava ./test/src --concurrency 4",
     "cover": "nyc --reporter=lcov npm test"
   },