Support Azure Devops

[Axosoft-Ashley]

Adds support for Azure Devops, not to be confused with Azure AD

To create a new Azure Devops app for local stack:

1. Go to https://app.vsaex.visualstudio.com/app/register.
2. Enter whatever company name you would like.
3. Name your application whatever you would like.
4. Set your application website to http://localhost:8080
5. Set your callback url Note: This url MUST be https which will throw erros when developing locally. One work around is to directly manipulate the url when your browser attempts to redirect.
6. Set Scopes

goth.UseProviders(
azuredevops.New(os.Getenv("AZUREDEVOPS_KEY"), os.Getenv("AZUREDEVOPS_SECRET"), "http://localhost:3000/auth/azuredevops/callback"),
)