Sugar for Options

It would be great to have support like Kotlin's for Option types. Specifically:

• T? as sugar for Option[T]
• Support an implicit conversion from T to T?
• ?. propagates None
• Somehow get a None value to work for all T. Could build in, or is it safe to make None[Dyn] <: None[T] for all T?
• ?: specifies a value to use if the LHS is None
• ! transforms T? to T, raising an error in the case of None