fix Makefile and README.md for 2000/natori

There was an attempt to get natori.c to compile.
We moved the 2 includes to the compile line
restoring the code as a 1-liner.

We forced the types of args iun main to conform to
bogons introduced by the ANSI-C committee.

Nevertheless, the code still fails to compile:

    assignment to cast is illegal, lvalue casts are not supported

This will be a TODO fix for later.

2000/natori/natori.c

@@ -1,3 +1 @@
-#include <stdio.h>
-#include <math.h>
-double l;main(_,o,O){return putchar((_--+22&&_+44&&main(_,-43,_),_&&o)?(main(-43,++o,O),((l=(o+21)/sqrt(3-O*22-O*O),l*l<4&&(fabs(((time(0)-607728)%2551443)/405859.-4.7+acos(l/2))<1.57))[" #"])):10);}
+double l;main(int _,char**o,char**O){return putchar((_--+22&&_+44&&main(_,-43,_),_&&(int)o)?(main(-43,++(int)o,(int)O),((l=((int)o+21)/sqrt(3-(int)O*22-(int)O*(int)O),l*l<4&&(fabs(((time(0)-607728)%2551443)/405859.-4.7+acos(l/2))<1.57))[" #"])):10);}