[WIP] Enable self-sizing for component in SwiftUI

[ra1028]

TODO

• Enable self-sizing
• Add ReferenceSizeComponentWrapper.
• Remove Component.intrinsicContentSize(for:) added in RC5
• Add or remove tests.
• Update README and docs

Checklist

• All tests are passed.
• Added tests.
• Documented the code using Xcode markup.
• Searched existing pull requests for ensure not duplicated.

Description

SwiftUI can't support self-sizing, but we can one approach that calculating the size of content at the appearing event with GeometryReader in background.

Related Issue

N/A

Motivation and Context

Further clear and intuitive API for the Carbon component in the SwiftUI.

Impact on Existing Code

Remove Component.intrinsicContentSize(for:) added in RC5

Screenshots (if appropriate)

struct KyotoTop_Previews: PreviewProvider {
    static var previews: some View {
        KyotoTop()
    }
}