1999-05-03  Jukka-Pekka Iivonen  <iivonen@iki.fi>

	* src/fn-database.c: New file added for database
 	functions. Implemented DAVERAGE(), DCOUNT(), DGET(), DMAX(),
 	DMIN(), DPRODUCT(), DSTDEV(), DSTDEVP(), DSUM(), DVAR(), and
 	DVARP().

	* src/func.c: Added registeration of database functions.

	* src/fn-stat.c, src/func.h: callback_function_stat made public.