Fix quickstart example

[simeoncarstens]

Closes #153.

[donaldcampbelljr]

Oh yes. I see the problem. We also began moving towards using JSON schema for the output schemas (while still supporting the old style). I suggest we go ahead and change this readme to have that format:

title: An example Pipestat output schema
description: A pipeline that uses pipestat to report sample and project level results.
type: object
properties:
  pipeline_name: "default_pipeline_name"
  samples:
    type: object
    properties:
        result_name:
          type: string
          description: "ResultName"