fix: VcViewer baseLayer bug, make baselayer prop works with `false` value

[longhewang]

VcViewer 修复:base-layer="false"时没有禁用基础图层的bug 同步更新文档 修复文档说明中的拼写错误baseelayerpicker->baseLayerPicker

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[zouyaoji]

hi @longhewang，非常感谢您的 PR ，但是您没有使用 PR 标题规则 格式，请及时修改， 谢谢！

[zouyaoji]

hi @longhewang，非常感谢您及时修正标题格式，祝您玩的开心！