Hey,
If I remember correctly I got them from the german knx-user-forum.de thread. Most of the links to cloudbees are broken now. Possibly the one from speedy.sh still works. I can also send you my files, in case you have tough luck. Or compile the source on your own.
the caldav binding is not yet merged into the master that is because you won’t find it on cloudbees, yet. As soon as we’ve managed to finalise the review this binding will be available for you. Meanwhile feel free to checkout the given fork and build the binding(s) yourself.