VictoryStack Custom Baseline Support

[jhumbug]

Adds support for supplying custom baselines (y0) to the first child in a set of VictoryStack wrapped components, so that they stack correctly based on that first dataset.

Example:

<VictoryChart>
  <VictoryStack>
    <VictoryArea
      style={{ data: { fill: "red" } }}
      data={[
        { x: 1, y: 2, y0: 1 },
        { x: 2, y: 1, y0: -2 },
        { x: 3, y: 4, y0: 1 },
        { x: 4, y: 2, y0: -3 }
      ]}
    />
    <VictoryArea
      data={[
        { x: 1, y: 2 },
        { x: 2, y: 1 },
        { x: 3, y: 4 },
        { x: 4, y: 2 }
      ]}
    />
    <VictoryArea
      data={[
        { x: 1, y: 2 },
        { x: 2, y: 1 },
        { x: 3, y: 4 },
        { x: 4, y: 2 }
      ]}
    />
    <VictoryArea
      data={[
        { x: 1, y: 1 },
        { x: 2, y: 4 },
        { x: 3, y: 3 },
        { x: 4, y: 8 }
      ]}
    />
  </VictoryStack>
</VictoryChart>

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[boygirl]

@jhumbug perfect! I love a straightforward change. Can you also add your example as a story?

[boygirl]

Nice work!