ASAN and vfork() don't appear to play well together. Maybe in later
versions of GCC it'll be better. But vfork() is flirting with danger
after all and that probably doesn't make sense in ASAN mode anyway.
- Fix regression with `%lu`
- Added some more headers witnessed in the wild
- Added `-M INT` option to redbean to tune max payload size
- Work around InfoZIP 256 character limit on comment line size
