wait-on 3.3.0

on Node.js NPM

• Added --httpTimeout option

--httpTimeout

  Maximum time in ms to wait for an HTTP HEAD/GET request, default 0
  which results in using the OS default

• Upgraded dependencies: #38, thanks @matijagaspar

• Require Node Version +8.9.0: #33

Thanks to @valscion for summarizing the release notes.
Also thanks to @perry-mitchell for mentioning that this should have been a major release bump due to dropping support for Node 6. Node 6 users should use v3.2.0. In the future, I will bump major version when Node version support changes.