How to style NSTextView and NSTextField in macOS

Issue #443

let textField = NSTextField()
textField.focusRingType = .none

let textView = NSTextView()
textView.insertionPointColor = R.color.caret
textView.isRichText = false
textView.importsGraphics = false
textView.isEditable = true
textView.isSelectable = true
textView.drawsBackground = false
textView.allowsUndo = true