Make improvements

- Emulator can now test the αcτµαlly pδrταblε εxεcµταblε bootloader

- Whipped up a webserver named redbean. It services 150k requests per
  second on a single core. Bundling assets inside zip enables extremely
  fast serving for two reasons. The first is that zip central directory
  lookups go faster than stat() system calls. The second is that both
  zip and gzip content-encoding use DEFLATE, therefore, compressed
  responses can be served via the sendfile() system call which does an
  in-kernel copy directly from the zip executable structure. Also note
  that red bean zip executables can be deployed easily to all platforms,
  since these native executables work on Linux, Mac, BSD, and Windows.

- Address sanitizer now works very well

libc/sock/setsockopt.c

@@ -51,7 +51,7 @@ static textwindows int setsockopt$nt(struct Fd *fd, int level, int optname,
  *   int yes = 1;
  *   setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &yes, sizeof(yes));
  *
- * @param level can be SOL_SOCKET, IPPROTO_TCP, etc.
+ * @param level can be SOL_SOCKET, SOL_IP, SOL_TCP, etc.
  * @param optname can be SO_{REUSE{PORT,ADDR},KEEPALIVE,etc.} etc.
  * @return 0 on success, or -1 w/ errno
  * @error ENOPROTOOPT for unknown (level,optname)
@@ -60,6 +60,7 @@ static textwindows int setsockopt$nt(struct Fd *fd, int level, int optname,
  */
 int setsockopt(int fd, int level, int optname, const void *optval,
                uint32_t optlen) {
+  if (!optval) return efault();
   if (!level || !optname) return enoprotoopt(); /* our sysvconsts definition */
   if (optname == -1) return 0;                  /* our sysvconsts definition */
   if (!IsWindows()) {