[G-API] Handle exceptions in streaming executor

* Handle exceptions in streaming executor

* Rethrow exception in non-streaming executor

* Clean up

* Put more tests

* Handle exceptions in IE backend

* Handle exception in IE callbacks

* Handle exception in GExecutor

* Handle all exceptions in IE backend

* Not only (std::exception& e)

* Fix comments to review

* Handle input exception in generic way

* Fix comment

* Clean up

* Apply review comments

* Put more comments
* Fix alignment
* Move test outside of HAVE_NGRAPH

* Fix compilation