Adapt FlightVars module to latest changes

Fixes issue #13. FlightVars entry point has been modified in order to
initialize the objects according to the latest changes: init a IO service
object and use it to initialize the tick observer and the TCP server.

In addition, several bugs and issues have been detected and fixed.

 - `flight_vars_core` was using deprecated `ptr` template class rather
   than `std::shared_ptr`. All `ptr` usages have been replace by
   `std::shared_ptr`.
 - FSUIPC client library was compiled with UNICODE support, failing to
   pass the correct Window name for accessing the UIPC service. Fixed by
   making the Window name depend on the use of Unicode.
 - `fsuipc_client` was sending a `process()` request even when no data was
   to read or write. That throws an exception for
   `local_fsuipc_user_adapter`. Fixed by doing no work when no input is
   requested for `query()` and `update()`.