feat: upgrade q from 1.5.0 to 2.0.3

Snyk has created this PR to upgrade q from 1.5.0 to 2.0.3.

See this package in npm:
q

See this project in Snyk:
https://app.snyk.io/org/okeamah/project/24701a0c-6fb4-466c-8926-34dc43134447?utm_source=github&utm_medium=referral&page=upgrade-pr

package.json

@@ -5,7 +5,7 @@
  "description": "CLI to generate books and documentation using gitbook",
  "main": "bin/gitbook.js",
  "dependencies": {
- "q": "1.5.0",
+ "q": "2.0.3",
  "lodash": "4.17.4",
  "semver": "5.3.0",
  "npmi": "1.0.1",