Add ASIO_NO_DEPRECATED test around io_service::reset().
Add get_executor() to I/O objects.
Remove previously deprecated functions and classes.
Update basic_waitable_timer to proposed interface.
Enable move-only handlers.

All async operations and executor operations support move-only
handlers. However, the io_service::post(), io_service::dispatch(),
io_service::strand::post() and io_service::strand::dispatch() functions
still require copyable handlers.
Fix Windows build.