When is snow coming?

The ptp2 driver uses for historic reasons in its PTP code various layers
of indirection.
master transaction function -> protocol (USB or PTP/IP) specific action func -> io interface function

Now the idea was to swap out the io interface function for different users. And thats what
libmtp and we did for a while. However, it did not really work out, we started to have
wild hacks in the protocol specific action function. Also ptp/ip already used
different protocol specific action function.

So now it looks like:
master transaction function -> protocol and lowlevel io specific function

The protocol handling is to some degree now duplicated between libmtp and libgphoto2,
but its clearer... And the progress handling can now be done for both in their seperate versions. Code is also cleaner (strange enough). And some MTP bugs fixed too I hope.

Spent the afternoon going to Nuernberg Airport (NUE/EDDN) ... was too crowded for me, since they have an open no-cost icerink where like 100 families with kids were hanging around. Walked through Whoerder Wiese Park to home.