Added librarys and test application

include/entityx/System.cc

@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2012 Alec Thomas <alec@swapoff.org>
+ * All rights reserved.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution.
+ *
+ * Author: Alec Thomas <alec@swapoff.org>
+ */
+
+#include "entityx/System.h"
+
+namespace entityx {
+
+BaseSystem::Family BaseSystem::family_counter_;
+
+BaseSystem::~BaseSystem() {
+}
+
+void SystemManager::update_all(TimeDelta dt) {
+  assert(initialized_ && "SystemManager::configure() not called");
+  for (auto &pair : systems_) {
+    pair.second->update(entity_manager_, event_manager_, dt);
+  }
+}
+
+void SystemManager::configure() {
+  for (auto &pair : systems_) {
+    pair.second->configure(entity_manager_, event_manager_);
+  }
+  initialized_ = true;
+}
+
+}  // namespace entityx