ThrottleRequestFilter swallows interfaces

[markus-s24]

The ThrottleRequestFilter wraps the AsyncHandler with an AsyncHandlerWrapper. This way all additional interfaces implemented by the originating AsyncHandler get lost. E.g. ProgressAsyncHandler, ResumableAsyncHandler or any custom interfaces.

Suggestion: Maybe use a dynamic proxy which implements all interfaces of the originating AsyncHandler instead of using AsyncHandlerWrapper.

[slandelle]

The Filter API comes from the original author of this library.
I have personally no use for it so far.

Contributions welcome

[markus-s24]

See #1315