Feature request: do not generate default clause.

[safareli]

First of all thanks for this extension it's very useful!

Curious what's the point of default clause in generated code? As this plugin is listing out all the cases I don't see one. Default is just unreachable. I would like to propose to remove the default clause, or add a flag that would allow to override this behavior.

Thanks!

[heroboy]

Although typescript is a strict language. But due to any, type cast and being called from javascript, we should always write the default for safety.
And typescript compiler doesn't tell the default clause is unreachable, when the case clauses enumerate all possible values.

[safareli]

I use strict mode and do not use any. and I don't need to use default. It's ok if you want this plugin to be opinionated, but I think if you were to add flag to toggle this feature, this plugin would be more attractive to people who do not want default clause.