tools/scratch: remove inadvertantly committed code

scratch should always be a noop. It's only here to simplify testing of
new code.

tools/scratch.cpp

@@ -1,21 +1,8 @@
-#include <cstdlib>
-
-#include <iostream>
-
-#include "coord/iostream.hpp"
-#include "extent.hpp"
-#include "region.hpp"
-
 int
 main (int argc, char **argv)
 {
     (void)argc;
     (void)argv;
 
-    util::point2u a { 0, 0 };
-    util::point2u b { 1, 1 };
-    util::region2u v { a, b };
-    std::cerr << v << '\n';
-
     return EXIT_SUCCESS;
 }