Spring Support 'default' option in StringToTimeZoneConverter

Originally raised in in Spring Boot it would be nice if our StringToTimeZoneConverter could support "default" -> TimeZone.getDefault().

Comment From: philwebb

We discussed this a little on our call and considered that most users server-side applications shouldn't be using TimeZone.getDefault(). However, I'm not sure if that's a strong enough argument for the fact that we don't offer converter support for it.

Comment From: snicoll

Thanks for the suggestion but we feel that returning the default timezone based on "default" to be a bit too magical.