returns the effective one, and checkRoi does both withouth hw changes
* finished implementation of Frelon::Camera trigger mode, expusure
  and latency times, nb of frames and start/stop
* added user FrameCallback to Espia::Acq; renamed AcqStatus -> Status
* implemented Espia::BufferMgr wich concat frames and callbacks
* added concat frames in buffer mgrs allocBuffers and getBufferPtr
* changed [un]registerCallback in HwFrameCallbackGen (and derived)
  to recieve a reference to the callback object instead of its pointer
* extended and moved GetDefMaxNbBuffers and ClearBuffer to MemUtils;
  buffer managers now have them as default implementation
* print HwFrameInfoType::frame_timestamp with microsecond resolution;
  added ostream << X/YBorder and Corner operators



git-svn-id: https://scm.blissgarden.org/svn/lima/trunk@81 45c4679d-1946-429d-baad-37912b19538b