Merge branch 'master' into release

  * bumped interface version to 4
  * timeout parameter removed from Close()/cec_close(). return type changed to
    void
  * added cec_destroy() method
  * removed timeout parameter from Transmit()
  * change the default argument of PowerOnDevices() to CECDEVICE_TV
  * removed PowerOffDevices(). use StandbyDevices() instead
  * removed obsolete methods from the interface
  * fixed bug: pthread_cond_wait was called without the mutex locked
  * fixed possible deadlock: don't send messages and wait for an ack with the
    mutex locked in CCECParser
  * created a separate reader thread and fixed the 'lock timeout' bug
  * testclient: use CECDEVICE_TV instead of the default argument
    (CECDEVICE_BROADCAST) for PowerOnDevices() and PowerOffDevices()