Introduce ctl::set and ctl::map

We now have a C++ red-black tree implementation that implements standard
template library compatible APIs while compiling 10x faster than libcxx.
It's not as beautiful as the red-black tree implementation in Plinko but
this will get the job done and the test proves it upholds all invariants

This change also restores CheckForMemoryLeaks() support and fixes a real
actual bug I discovered with Doug Lea's dlmalloc_inspect_all() function.

test/ctl/optional_test.cc

@@ -17,11 +17,10 @@
 // PERFORMANCE OF THIS SOFTWARE.
 
 #include "ctl/optional.h"
+#include "libc/mem/leaks.h"
 
 #include "ctl/string.h"
 
-#include "libc/runtime/runtime.h"
-
 // #include <optional>
 // #include <string>
 // #define ctl std
@@ -131,5 +130,4 @@ main()
     }
 
     CheckForMemoryLeaks();
-    return 0;
 }