https://bugs.eressea.de/view.php?id=2225
The Lua markets module is wrong, so the C code is being used.
Disable the Lua module for now, either fix or delete it later?
1. all log messages will be terminated with \n, whether the user provided
it or not.
2. remove a bunch of print() calls from scripts to reduce clutter
3. replace printf calls with log_* calls to reduce clutter
4. add the new release preview script
