Synopsys   : FILTER_RACE(x, r)

Defined in : /sys/filter_funs.h

Description: This filter returns an array with only those objects that are
             of the requested race. Note that unless any object would happen
             to define the function query_race_name() and return the proper
             race as answer you are not likely to get any non-livings in the
             resulting array.
Arguments  : object *x - the array with objects to filter.
             string r  - the race to check for.
Returns    : object *  - an array with only objects of race 'r' in it.
