createLabel method
Creates a new label on the specified repository.
API docs: https://developer.github.com/v3/issues/labels/#create-a-label
Implementation
Future<IssueLabel> createLabel(
RepositorySlug slug, String name, String color) {
return github.postJSON('/repos/${slug.fullName}/labels',
body: GitHubJson.encode({'name': name, 'color': color}),
convert: (dynamic i) => IssueLabel.fromJson(i));
}