Implement VSpace, HSpace, Space

VStack {
    View1()
    VSpace(16) // adds 16pt empty view
    View2()
}

HStack {
    View1()
    HSpace(16) // adds 16pt empty view
    View2()
}

HStack {
    View1().width(100)
    View2().width(32)
    Space() // adds flexible empty view
}