First class support for F#

It would be nice if wit-bindgen could have first class support for F#. Since wit-bindgen already supports C#, I've managed to come up with something a little hacky so that F# can call imported functions defined in WIT (https://github.com/bytecodealliance/componentize-dotnet/issues/92).

However, this approach is not only rather cumbersome, it also does not allow exporting functions from F#.

Since wit-bindgen already supports C#, naively I would expect adding F# support should not be so difficult, but would be more of a matter of just adjusting the C# syntax to F#.