chore(package): update p-event to version 2.0.0

Author: greenkeeper[bot]

package.json

@@ -79,7 +79,7 @@
  "json-schema": "0.2.3",
  "lint-staged": "^7.0.0",
  "mock-fs": "^4.4.2",
- "p-event": "^1.3.0",
+ "p-event": "^2.0.0",
  "prettier": "^1.10.2",
  "regenerator-runtime": "^0.11.1",
  "standard-version": "^4.3.0",