allows hide Github and Social links in docs layout

[skaldarnar]

• adds setting key micrositeShareOnSocial whether to show/hide the
  share on social buttons in docs layout
• adds setting key micrositeGithubLinks whether to show/hide GitHub
  links for stars and forks in docs layout

Please let me know whether you are fine with this addition or if I'm missing something. Also, naming and correct locations for the settings are up for discussion…

[calvellido]

Hi, thank you very much @skaldarnar, these are really good additions to the features list of the project.

A couple things before merging. Would you be so kind to add these new feature to the documentation also? Probably the best location for them will be here:

https://github.com/skaldarnar/sbt-microsites/blob/feature/customize-docs-layout/docs/src/main/tut/docs/settings.md

Also, as the way tests are set in the project, could you also add these new settings to the arbitraries?

https://github.com/skaldarnar/sbt-microsites/blob/feature/customize-docs-layout/src/test/scala/microsites/util/Arbitraries.scala

Thanks!

[skaldarnar]

Thanks for your feedback.

I hope this fully addresses your change requests. If anythin is left, please let me know.

[calvellido]

Awesome @skaldarnar, thank you very much. Will merge and release a new version including the two new features 🎉!