virtual destructors to avoid compiler warnings
* Renamed SoftBufferCtrlMgr helper class to SoftBufferCtrlObj;
  created SoftBufferCtrlObj::Sync::BufferList type name.
* Updated SoftBufferCtrlObj usage in HwVideoCtrlObj, and in
  Simulator, Basler, Prosilica, PCO, Mythen and RoperScientific plugins
* Removed unused Mythen and RoperScientific BufferCtrlObjs;
  using (good) Camera SoftBufferCtrlObj in Interface::reset
* Added HwBufferCtrlObj::Callback virtual destructor;
  moved virtual HwBufferMgr/CtrlObj methods outside class declaration
* Started generic Event interface for asynchronous notification, including:
  + basic info: layer, severity, domain, code and description
  + timestamps: absolute and relative to the last acq. start
  + simple structure based on one event callback and one generator
  + debug infrastructure support
  + new HwCap::Event and corresponding HwEventCtrlObj callback generator
  + basic CtEvent support: abort acq. on fatal or error events,
    user can either retrieve the events (C++) or register to event callbacks
  + current Event::Code is based on CtControl::ErrorCode/CameraErrorCode
* Implemented DebProxy copy constructor, necessary for DEB_HWEVENT
* Protect CtAcquisition against invalid nb. of stripe concat. frames
* Allow Live acq. in stripe concat. mode; use default (16) nb. of buffers
* Verify HwFrameCallback return code, given by control layer during
  preliminary frame processing, to abort Espia acquisition from callback
* Added EventCallback support to Espia::Acq, notifing Espia callback errors,
  in particular buffer overrun conditions
* Implemented Frelon EventCtrlObj, redirecting EventCallbacks from Espia::Acq
* Using Frelon TimeUnit (Z) register to properly handle ShutterCloseTime and
  LatencyTime, which before were (mistakenly) assumed to be in Milliseconds
* Verify Frelon model before issuing SPB2-specific commands (ConfigHD, HTD)
* Using DEB_HEX() when displaying Frelon available modes (CMA)
* Removed manual stopAcq when AcqFault is found in FrelonTacoAcq::getState
* Set a valid nb_concat_frames when configuring a Live (endless)
  FrelonTacoAcq in StripeConcat mode
* Updated Frelon, Maxipix & Focla DetInfoCtrlObj to support
  rectangular pixel sizes