fix for https://bugs.eressea.de/view.php?id=1993
removing a lot of mallocs through strdup by replacing getcommand calls with get_command, which takes a buffer. only one left. removing mkname calls with a static buffer for keyword-tokens. commit the schema file I had lying around.
add tests for keyword.c, incomplete.
direction parser gets new initialization function, for use in jsonconf later. add unit tests for directions.