Edit babel settings to produce node v.4+ compatible code

Author: jmike

.babelrc

@@ -1,9 +1,7 @@
 {
-  "presets": ["node5"],
+  "presets": ["es2015"],
   "plugins": [
-    "typecheck",
-    "syntax-flow",
-    "transform-flow-strip-types",
-    "add-module-exports"
+    "add-module-exports",
+    "transform-es2015-modules-commonjs"
   ]
 }

package.json

@@ -13,7 +13,7 @@
     "test": "node test/index.js"
   },
   "engines": {
-    "node": ">=5.0.0"
+    "node": ">=4.0.0"
   },
   "dependencies": {
     "bluebird": "^3.3.4",
@@ -25,12 +25,11 @@
   },
   "devDependencies": {
     "babel": "^6.5.2",
-    "babel-core": "^6.7.4",
+    "babel-cli": "^6.7.5",
+    "babel-core": "^6.7.7",
     "babel-plugin-add-module-exports": "^0.1.2",
-    "babel-plugin-syntax-flow": "^6.5.0",
-    "babel-plugin-transform-flow-strip-types": "^6.7.0",
-    "babel-plugin-typecheck": "^3.8.0",
-    "babel-preset-node5": "^11.0.0",
+    "babel-plugin-transform-es2015-modules-commonjs": "^6.7.7",
+    "babel-preset-es2015": "^6.6.0",
     "chai": "^3.5.0",
     "chai-as-promised": "^5.3.0",
     "dotenv": "^2.0.0",