Make build hermetic without shell scripts

- Fix some minor issues in ar.com
- Have execve() look for `ape` command
- Rewrite NT paths using /c/ rather /??/c:/
- Replace broken GCC symlinks with .sym files
- Rewrite $PATH environment variables on startup
- Make $(APE_NO_MODIFY_SELF) the default bootloader
- Add all build command dependencies to build/bootstrap
- Get the repository mostly building from source on non-Linux

test/libc/runtime/mmap_test.c

@@ -24,6 +24,7 @@
 #include "libc/dce.h"
 #include "libc/errno.h"
 #include "libc/fmt/fmt.h"
+#include "libc/intrin/kprintf.h"
 #include "libc/linux/mmap.h"
 #include "libc/linux/munmap.h"
 #include "libc/log/log.h"
@@ -228,6 +229,7 @@ TEST(mmap, cow) {
   char *p;
   char path[PATH_MAX];
   sprintf(path, "%s%s.%ld", kTmpPath, program_invocation_short_name, lemur64());
+  kprintf("path = %#s\n", path);
   ASSERT_NE(-1, (fd = open(path, O_CREAT | O_TRUNC | O_RDWR, 0644)));
   EXPECT_EQ(5, write(fd, "hello", 5));
   EXPECT_NE(-1, fdatasync(fd));