This change fixes Cosmopolitan so it has fewer opinions about compiler
warnings. The whole repository had to be cleaned up to be buildable in
-Werror -Wall mode. This lets us benefit from things like strict const
checking. Some actual bugs might have been caught too.
This change improves the way internal APIs are being hidden behind the
`COSMO` define. The cosmo.h header will take care of defining that, so
that a separate define statement isn't needed. This change also does a
lot more to define which APIs are standard, and which belong to Cosmo.
- Better UBSAN error messages
- POSIX Advisory Locks polyfills
- Move redbean manual to /.help.txt
- System call memory safety in ASAN mode
- Character classification now does UNICODE
