Remove Exception support?

[glureau]

A previous experimentation has been pushed on Exceptions.

It was practical for our use case at the time but it's leading to more and more subtle issues that we don't want to support. Also it worked only when passing the exception in a method/property, but it cannot be wrapped when a throw is done from Typescript, meaning that a try/catch on the Kotlin will still have to deal with the Typescript Error and not the wrapped exception.

From our learnings, we think it's better to have explicit API with types that don't extends Exception. And if we need to pass it, we'll let KotlinJs deal with it and not trying to interfere here. But for that we need #19 and #17 to be fixed.

As a bonus, it should also reduce the bundle size.

[glureau]

Exceptions are no more handled by KustomExport, starting from v0.5.0