Implement support for repository visibility parameter

[patrickmarabeas]

Implements support for specifying a repositories visibility. It can be
one of public, private or internal (if the organization is associated
with an enterprise account).

The associated preview header (nebula) has also been added.

Resolves: #1470

[codecov]

Codecov Report

Merging #1471 into master will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1471      +/-   ##
==========================================
+ Coverage   68.16%   68.17%   +0.01%     
==========================================
  Files          94       94              
  Lines        8419     8422       +3     
==========================================
+ Hits         5739     5742       +3     
  Misses       1819     1819              
  Partials      861      861              

Impacted Files	Coverage Δ
github/github.go	89.77% <ø> (ø)
github/repos.go	69.81% <100.00%> (+0.14%)	⬆️

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[patrickmarabeas]

What is the release cadence for this project - I would like to put this to use in the Github Terraform Provider ASAP!

[gmlewis]

We used to do a semver (major, minor, patch) release on each merged PR, but that got way too extreme... so now we release on demand. I can make a new release after this PR is merged.

[gmlewis]

Thank you, @patrickmarabeas!
LGTM.

Awaiting second LGTM before merging.

Note to self: this is a non-breaking API change, and adds backward-compatible functionality, so this will be a minor release.

[patrickmarabeas]

That would be great - thanks @gmlewis!

[wesleimp]

LGTM 👌

[gmlewis]

Thank you, @wesleimp!
Merging, then making a minor release.

[gmlewis]

@patrickmarabeas - Version v30.1.0 has now been released at your request.