fix(package): update node requirement to 8.3

pvdlg · gr2m · commit bd2908d5aa6c · 2018-02-09T14:52:47.000-08:00
diff --git a/package.json b/package.json
@@ -42,7 +42,7 @@
     "xo": "^0.18.2"
   },
   "engines": {
-    "node": ">=4"
+    "node": ">=8.3"
   },
   "files": [
     "lib",
