Remove unneeded #included files in 2001/anonymous

These were part of debugging the reason execv() did not run the target
program but I forgot to remove them once I found out it was a text file
busy error.

Also added to README.md another git diff to try as it might be
instructive.

2001/anonymous/anonymous.c

@@ -5,8 +5,6 @@
 #include <stdlib.h>
 #include <strings.h>
 #include <sys/mman.h>
-#include <string.h>
-#include <errno.h>
 
 #define l int*
 #define F char