modified check_all_args(), should be much more flexible now

Rev: src/ChangeLog:1.88
Rev: src/interpret.c:1.36
Rev: src/language.yacc:1.32
Rev: src/lex.c:1.19
Rev: src/mapping.c:1.15
Rev: src/module_support.c:1.4
Rev: src/module_support.h:1.4
Rev: src/modules/Yp/yp.c:1.4
Rev: src/modules/files/file.c:1.30
Rev: src/modules/system/system.c:1.14
Rev: src/operators.c:1.12
Rev: src/peep.in:1.7
Rev: src/pike_types.c:1.19
Rev: src/svalue.h:1.7