Fixed missing checks for NULL from gmtime(2), localtime(2) and ctime(2) which could cause segfaults. E.g. on NT they don't handle negative time stamps. Rev: src/builtin.cmod:1.91 Rev: src/modules/HTTPLoop/log.c:1.11 Rev: src/modules/Oracle/oracle.c:1.71 Rev: src/modules/spider/discdate.c:1.11