Remove package.json5 file

Attempting to keep package.json and package.json5 in sync proves
difficult, especially when running `npm version`. The package.json5 file
will be removed until an easier way to maintain it is developed.

Author: jordanbtucker

build/check-package.js

@@ -16,7 +16,7 @@
     "prepublishOnly": "npm run lint && npm test && npm run production",
     "pretest": "cross-env NODE_ENV=test npm run build",
     "preversion": "npm run lint && npm test && npm run production",
-    "production": "cross-env NODE_ENV=production npm run build && babel-node build/check-package.js",
+    "production": "cross-env NODE_ENV=production npm run build",
     "test": "nyc --reporter=html --reporter=text mocha"
   },
   "repository": {