Log Message:
Update to 0.6.16. Changes since 0.6.15:

* For ccid, etoken* drivers remove polling loop, review the force_poll
  configuration option, this reduces power consumption and CPU load.
* Fix some issues caused by newer udev version.
* Handle T1 abort better.
* Some build system fixes.
* Some minor fixes.
* Re-add api documentation (pre-generated), like we used to.