Make exciting improvements

- Add Lua backtraces to redbean!
- Wipe serving keys after redbean forks
- Audit redbean to remove free via exit
- Log SSL client ciphersuite preferences
- Increase ASAN malloc() backtrace depth
- Make GetSslRoots() behave as a singleton
- Move leaks.c from LIBC_TESTLIB to LIBC_LOG
- Add undocumented %n to printf() for newlines
- Fix redbean memory leak reindexing inode change
- Fix redbean memory leak with Fetch() DNS object
- Restore original environ after __cxa_finalize()
- Make backtrace always work after __cxa_finalize()
- Introduce COUNTEXPR() diagnostic / benchmark tool
- Fix a few more instances of errno being clobbered
- Consolidate the ANSI color disabling internal APIs

libc/log/showcrashreports.c

@@ -72,7 +72,7 @@ void ShowCrashReports(void) {
   for (i = 0; i < ARRAYLEN(kCrashSigs); ++i) {
     sigdelset(&sa.sa_mask, kCrashSigs[i]);
   }
-  sigaltstack(&ss, 0);
+  if (!IsWindows()) sigaltstack(&ss, 0);
   for (i = 0; i < ARRAYLEN(kCrashSigs); ++i) {
     if (kCrashSigs[i]) {
       sa.sa_sigaction = (sigaction_f)__oncrash_thunks[i];