fix(package): update node-addon-api to version 0.6.3

Closes #4

Author: greenkeeper[bot]

package.json

@@ -29,7 +29,7 @@
   "dependencies": {
     "bindings": "^1.3.0",
     "compressing": "^1.2.3",
-    "node-addon-api": "^0.5.1",
+    "node-addon-api": "^0.6.3",
     "protobufjs": "^6.8.0",
     "urllib": "^2.24.0"
   },