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

third_party/linenoise/linenoise.mk

@@ -28,7 +28,8 @@ THIRD_PARTY_LINENOISE_A_DIRECTDEPS =				\
 	LIBC_SYSV_CALLS						\
 	LIBC_STR						\
 	LIBC_UNICODE						\
-	LIBC_STUBS
+	LIBC_STUBS						\
+	NET_HTTP
 
 THIRD_PARTY_LINENOISE_A_DEPS :=					\
 	$(call uniq,$(foreach x,$(THIRD_PARTY_LINENOISE_A_DIRECTDEPS),$($(x))))