Add GitHub Reactions support

[TylerLeonhardt]

This adds the following cmdlets:

• Get-GitHubReaction - https://developer.github.com/v3/reactions/#list-reactions-for-an-issue
• Set-GitHubReaction - https://developer.github.com/v3/reactions/#create-reaction-for-an-issue
• Remove-GitHubReaction - https://developer.github.com/v3/reactions/#delete-an-issue-reaction

The Get and Set can pipe into Remove
Get-GitHubIssue can pipe into Get and Set-GitHubReaction

I also added some tests.

NOTE: commit comments will come later.

NOTE: DO NOT REMOVE THESE REACTIONS THEY ARE USED IN A TEST:

[HowardWolosky]

Thanks so much for starting this effort!

I haven't had a chance to review the tests yet. I'll do so shortly. In the meantime, I have some comments for you to review and address in the code.

Nice job with adding in pipeline support! I'm still mulling over the idea of PassThru and the implications that would have for the rest of the module.

[HowardWolosky]

Thanks -- will give a final pass at this tomorrow, and then hopefully get it merged in.

[HowardWolosky]

Super minor nits, then ready to go. Will kick off CI in the meantime.

[HowardWolosky]

/azp run PowerShellForGitHub-CI

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[HowardWolosky]

Static analysis failed:

##[warning]GitHubReactions.ps1(79,18): Warning : Command accepts pipeline input but has not defined a process block.
##[warning]GitHubReactions.ps1(84,17): Warning : Command accepts pipeline input but has not defined a process block.
##[warning]GitHubReactions.ps1(203,18): Warning : Command accepts pipeline input but has not defined a process block.
##[warning]GitHubReactions.ps1(208,17): Warning : Command accepts pipeline input but has not defined a process block.
##[warning]GitHubReactions.ps1(203,18): Warning : The parameter 'Uri' has been declared but not used. 
##[warning]GitHubReactions.ps1(216,18): Warning : The parameter 'NoStatus' has been declared but not used. 
##[warning]GitHubReactions.ps1(319,18): Warning : The parameter 'Uri' has been declared but not used. 
##[warning]GitHubReactions.ps1(330,18): Warning : The parameter 'NoStatus' has been declared but not used. 

[TylerLeonhardt]

/azp run PowerShellForGitHub-CI

[azure-pipelines]

Commenter does not have sufficient privileges for PR 193 in repo microsoft/PowerShellForGitHub

[HowardWolosky]

Now that #242 is in, we have a standard way for handling the pipeline throughout the module. Are you willing to update this PR to adopt it? Thanks.

[HowardWolosky]

Thanks for the update and getting this aligned with the rest of the module's pipeline support after #242. Looks like there just a few more updates to make before this is ready to go in.

[HowardWolosky]

/azp run PowerShellForGitHub-CI

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[HowardWolosky]

/azp run PowerShellForGitHub-CI

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[TylerLeonhardt]

any thoughts?

[HowardWolosky]

any thoughts?

I was waiting for you to post an update removing the comments support just for this PR so that we could get it in. Then we can work through a good design to add back the comments support. That keeps a good code flow going without having this PR specifically grow and grow and grow.

[TylerLeonhardt]

removed

[HowardWolosky]

/azp run PowerShellForGitHub-CI

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[TylerLeonhardt]

@HowardWolosky I don't think I impacted these failures

[HowardWolosky]

@HowardWolosky Howard Wolosky FTE I don't think I impacted these failures

Agreed -- there's some instability in a couple of the Repository tests that need to be investigated, but those are not considered blocking for getting this in. This should get merged today, and then we can work on adding-in comment support.

[HowardWolosky]

@TylerLeonhardt - Can you take a quick look at this file? It looks like the whole file changed. Likely an encoding issue. Would be great if you could get it updated in the PR such that it reflects just the changed lines. Might require you to revert the file and then re-apply the changes. I've noticed that using the GitHub web resolver does this to the file.

[TylerLeonhardt]

fixed

[HowardWolosky]

Awesome. Thanks for this!