Update vars_default.ps1

Environment variables to accompany GitLab.ps1 plugin

vars_default.ps1

@@ -4,3 +4,8 @@ $Env:Github_UserRepo   = ''   # Publish to Github; commit git changes
 $Env:Github_ApiKey     = ''   # Publish to Github token
 $Env:NuGet_ApiKey      = ''   # Publish to PSGallery token
 $Env:Chocolatey_ApiKey = ''   # Publish to Chocolatey token
+
+$Env:gitlab_user            = ''   # GitLab username to use for the push
+$Env:gitlab_api_key         = ''   # GitLab API key associated with gitlab_user
+$Env:gitlab_push_url        = ''   # GitLab URL to push to. Must be HTTP or HTTPS. e.g. https://jekotia:[email protected]/jekotia/au.git
+$Env:gitlab_commit_strategy = ''   # Same values as the Git plugin; single, atomic, or atomictag