Add lens correction with lensfun

Switch from libtiff to libdng

Remove gamma correction code

Bump version to 0.3.0

Make libtiff not crash on scary unknown numbers

Kill daemon at end of queue

Sequentialize the processing

Create a postprocessd daemon when none is running and delegate all the
work to that daemon. Reuse the daemon if it exists.

Integrate with Megapixels

Be more nice

Fix copy paste error in the documentation

Write first file and last

Renamed keep option

Option to only keep the last file in postprocess_internal

Restructured command line interafce

Make fork in listen_and_convert optional

Create daemon on first call

Process in fork

Moved make_socket_path

Single threaded listen function

Queue job by posting to socket