public Task AddReaction(string channel, string messageTimestamp, string reactionName)
{
var ts = new TaskCompletionSource <int>();
if (reactionName.StartsWith(":") && reactionName.EndsWith(":"))
{
reactionName = reactionName.Substring(1, reactionName.Length - 2);
}
Slack.AddReaction(
_ => { ts.SetResult(1); },
reactionName,
channel,
messageTimestamp);
return(ts.Task);
}