Fix bugs and make improvements

- Get clone() working on FreeBSD
- Increase some Python build quotas
- Add more atomic builtins to chibicc
- Fix ASAN poisoning of alloca() memory
- Make MODE= mandatory link path tinier
- Improve the examples folder a little bit
- Start working on some more resource limits
- Make the linenoise auto-complete UI as good as GNU readline
- Update compile.com, avoiding AVX codegen on non-AVX systems
- Make sure empty path to syscalls like opendir raises ENOENT
- Correctly polyfill ENOENT vs. ENOTDIR on the New Technology
- Port bestline's paredit features to //third_party/linenoise
- Remove workarounds for RHEL 5.0 bugs that were fixed in 5.1

libc/zip.h

@@ -200,7 +200,6 @@ uint64_t GetZipCfileCompressedSize(const uint8_t *);
 uint64_t GetZipCfileOffset(const uint8_t *);
 uint64_t GetZipLfileUncompressedSize(const uint8_t *);
 uint64_t GetZipLfileCompressedSize(const uint8_t *);
-uint8_t *zipfindcentraldir(const uint8_t *, size_t);
 void GetZipCfileTimestamps(const uint8_t *, struct timespec *,
                            struct timespec *, struct timespec *, int);