Log Message:
Update to 1.2.20

1.8.20: Ludovic Rousseau
30 December 2016
- Fix a crash and potential security issue in pcscd

1.8.19: Ludovic Rousseau
9 December 2016
- SCardGetStatusChange(): Fix a (rare) race condition
- Doxygen:
  . SCardGetStatusChange() may return SCARD_E_UNKNOWN_READER
  . SCardConnect() and SCardReconnect() will never return SCARD_E_NOT_READY
- pcsc-spy:
  . fix display of execution time
  . log the thread number in the results
- Some other minor improvements