anysniff: Expose the log_out/stat_out/console_out/syslog_out through a module struct.

[wdoekes]

Current situation

void out_help();
int out_open(char const *config_file);
void out_close();
void out_write(uint32_t unixtime_begin, uint32_t interval, void *data);

Wanted situation

struct output_module {
    void (*print_help)(FILE *fp);
    void (*open)(int argc, const char **argv); /* have it read argv directly */
    FILE *(*begin_summary)(); /* have it return something that the sniff modules can write to */
    void (*end_summary)();
    void (*close)();
};