fix: add uglify-js to production dependencies (#16)

Author: patrickmichalina

package-lock.json

@@ -62,10 +62,9 @@
     "prettier": "^1.13.5",
     "pretty-quick": "^1.6.0",
     "semantic-release": "^15.6.0",
-    "sinon": "^5.1.1",
+    "sinon": "^6.0.0",
     "tslint": "^5.10.0",
     "tslint-immutable": "^4.6.0",
-    "uglify-js": "^3.4.1",
     "validate-commit-msg": "^2.14.0",
     "zone.js": "^0.8.26"
   },
@@ -79,6 +78,7 @@
     "rxjs": "^6.2.1",
     "ts-node": "^6.1.2",
     "typescript": "^2.9.2",
+    "uglify-js": "^3.4.1",
     "yargs": "^11.0.0"
   },
   "release": {