deal with the output by removing params where possible and elsewhere
by adding XP_UNUSED macro wrapping __attribute__((unused)). There
should be NO change in function in spite of the large number of files.
support Slovak which has 40. This change is preliminary: it seems to
work for both existing and dicts with >32 chars, but it breaks backwards
compatibility: existing saved games will crash this code. I think the
fix is to deduce the number of bits per tile from the number in the
dictionary being used, but that's not in yet.