Update Documentation for Deploying Site in User Guide

[gerteck]

Please confirm that you have searched existing issues in the repo

Yes, I have searched the existing issues

What is the area that this feature belongs to?

Author Usability, Documentation

Is your feature request related to a problem? Please describe.

1. For Travis CI, the sample .travis.yml file in user guide documentation can be updated to remove the depreciated skip_cleanup key.

https://markbind.org/userGuide/deployingTheSite.html#deploying-via-travis-ci

deploy: deprecated key skip_cleanup (not supported in dpl v2, use cleanup)

2. Update Netlify Deployment Screenshots

https://markbind.org/userGuide/deployingTheSite.html#deploying-to-netlify

Minor changes have been made to the UI, including for environment variables (No longer under advanced build settings). Would be good to update the screenshots for greater clarity.

Additionally, can include info on Netlify dependency management on Node.js version in the UI as seen fit.

Describe the solution you'd like

Update documentation

[gerteck]

I believe this would fall under the labels of good first issue, d.easy, a-Documentation