working on async processing
working on async processing
working on async processing
working on async processing
working on async processing
working on async processing
made asynchronous request  body writing
added universal awaitable and awaiter due that TaskAwaitable and YieldAwaitable don't share base types and that Task<T> is not covariant
removed custom awaitables/awaters and put back Task as return value, instead added helper methods to run tasks synchronously
changed the way to create completed task - using FromResult and return base Task type.
adding testing and fixing async processing