Support ForEach

[melgu]

When using the HPageView with sperate views, it works as expected:

HPageView(selectedPage: $pageIndex) {
	Color.red
	Color.green
	Color.blue
}

But when trying to use ForEach, the PageView looks strange and only has one page indicator dot:

HPageView(selectedPage: $pageIndex, theme: pageTheme) {
	ForEach(0..<2) { n in
		Text("Number \(n)")
	}
}

[fredyshox]

ForEach-like init was added in release 1.5.0