Improved Documentation Local Testing

[artivilla]

So it wasn't clear to me that when you setup your serverless config config.json files the user has to match the bot property. I think the user should be the github. I was getting this err:

* artivilla/worktron: Failed to process work item: Error: Reject to process repo of different bot user (config.bot property)

[sokra]

It's a security measure to avoid two bugs talking with each other and resulting in many actions...