Make the DinkyECS test fully isolated.

tests/dinkyecs.cpp

@@ -2,12 +2,16 @@
 #include "dinkyecs.hpp"
 #include <iostream>
 #include <fmt/core.h>
-#include "point.hpp"
 
 using namespace fmt;
 using DinkyECS::Entity;
 using std::string;
 
+struct Point {
+  size_t x;
+  size_t y;
+};
+
 struct Player {
   string name;
   Entity eid;
@@ -17,35 +21,24 @@ struct Position {
   Point location;
 };
 
-// DINKY_HAS_COMPONENT(Point, x, y);
-// DINKY_HAS_COMPONENT(Position, location);
-
 struct Motion {
   int dx;
   int dy;
   bool random=false;
 };
 
-// DINKY_HAS_COMPONENT(Motion, dx, dy, random);
-
 struct Velocity {
   double x, y;
 };
 
-// DINKY_HAS_COMPONENT(Velocity, x, y);
-
 struct Gravity {
   double level;
 };
 
-// DINKY_HAS_COMPONENT(Gravity, level);
-
 struct DaGUI {
   int event;
 };
 
-// DINKY_HAS_COMPONENT(DaGUI, event);
-
 /*
  * Using a function catches instances where I'm not copying
  * the data into the world.