middleman-deploy mentioned in the current v4 docs is not compatible with MM4

[komor72]

https://middlemanapp.com/basics/build-and-deploy/#deploying-the-site page mentions the (very useful) plugin middleman-deploy, which is currently not compatible with Middleman v4. Should we remove it from the docs or is someone competent to renovate middleman-deploy to work with MM4?

[tysongach]

Yeah, probably wise to remove it. Would you like to submit a PR to do that?

[flexbox]

In fact you can deploy if you specify the master branch

Here is an example https://github.com/flexbox/davidl/blob/master/Gemfile#L17