Make some systemic improvements

- add vdso dump utility
- tests now log stack usage
- rename g_ftrace to __ftrace
- make internal spinlocks go faster
- add conformant c11 atomics library
- function tracing now logs stack usage
- make function call tracing thread safe
- add -X unsecure (no ssl) mode to redbean
- munmap() has more consistent behavior now
- pacify fsync() calls on python unit tests
- make --strace flag work better in redbean
- start minimizing and documenting compiler flags

libc/calls/sync.c

@@ -18,15 +18,22 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/calls/calls.h"
 #include "libc/calls/internal.h"
+#include "libc/calls/strace.internal.h"
 #include "libc/dce.h"
 
 /**
  * Flushes file system changes to disk by any means necessary.
+ * @see __nosync to secretly disable
  */
 void sync(void) {
-  if (!IsWindows()) {
-    sys_sync();
+  if (__nosync != 0x5453455454534146) {
+    if (!IsWindows()) {
+      sys_sync();
+    } else {
+      sys_sync_nt();
+    }
+    STRACE("sync()% m");
   } else {
-    sys_sync_nt();
+    STRACE("sync() → disabled% m");
   }
 }