Make more improvements

This change includes many bug fixes, for the NT polyfills, strings,
memory, boot, and math libraries which were discovered by adding more
tools for recreational programming, such as PC emulation. Lemon has also
been vendored because it works so well at parsing languages.

libc/calls/ioctl-default.c

@@ -29,8 +29,8 @@ int ioctl$default(int fd, uint64_t request, void *memory) {
   int64_t handle;
   if (!IsWindows()) {
     return ioctl$sysv(fd, request, memory);
-  } else if (isfdindex(fd)) {
-    if (isfdkind(fd, kFdSocket)) {
+  } else if (isfdopen(fd)) {
+    if (g_fds.p[fd].kind == kFdSocket) {
       handle = g_fds.p[fd].handle;
       if ((rc = weaken(__ioctlsocket$nt)(handle, request, memory)) != -1) {
         return rc;