* default_eventloop was prototyped in getdns_query and is still in there as my_eventloop
* It interfaces directly with the scheduling primitives of getdns.
* It can operate entirely from stack and does not have to do
any memory allocations or deallocations.
* Adapted configure.ac to allow libunbound to be linked with Windows
(with the removal of winsock_event.c we have no symbol clashed anymore)
* Added STUB_TCP_WOULDBLOCK return code in stub_resolving helper functions,
to anticipate dealing with edge triggered event loops (versus level triggered). (i.e. Windows)