Elevate Windows production worthiness

- SQLite file locking now works on Windows
- SQLite will now use fdatasync() on non-Apple platforms
- Fix Ctrl-C handler on Windows to not crash with TLS
- Signals now work in multithreaded apps on Windows
- fcntl() will now accurately report EINVAL errors
- fcntl() now has excellent --strace logging
- Token bucket replenish now go 100x faster
- *NSYNC cancellations now work on Windows
- Support closefrom() on NetBSD

libc/calls/getrusage-nt.c

@@ -33,7 +33,7 @@
 #include "libc/sysv/errfuns.h"
 
 textwindows int sys_getrusage_nt(int who, struct rusage *usage) {
-  int64_t me, nsignals;
+  int64_t me;
   struct NtIoCounters iocount;
   struct NtProcessMemoryCountersEx memcount;
   struct NtFileTime ftExit, ftUser, ftKernel, ftCreation;
@@ -48,9 +48,6 @@ textwindows int sys_getrusage_nt(int who, struct rusage *usage) {
       !GetProcessIoCounters(me, &iocount)) {
     return __winerr();
   }
-  __sig_lock();
-  nsignals = __sig_count;
-  __sig_unlock();
   *usage = (struct rusage){
       .ru_utime = WindowsDurationToTimeVal(ReadFileTime(ftUser)),
       .ru_stime = WindowsDurationToTimeVal(ReadFileTime(ftKernel)),