重构项目结构：整理gitignore，移动source目录到根目录，统一依赖管理

src/Utils/Timers/Timer.ts

@@ -0,0 +1,56 @@
+import { ITimer } from './ITimer';
+import { Time } from '../Time';
+
+/**
+ * 私有类隐藏ITimer的实现
+ */
+export class Timer implements ITimer{
+    public context: any;
+    public _timeInSeconds: number = 0;
+    public _repeats: boolean = false;
+    public _onTime!: (timer: ITimer) => void;
+    public _isDone: boolean = false;
+    public _elapsedTime: number = 0;
+
+    public getContext<T>(): T {
+        return this.context as T;
+    }
+
+    public reset(): void {
+        this._elapsedTime = 0;
+    }
+
+    public stop(): void {
+        this._isDone = true;
+    }
+
+    public tick(){
+        // 如果stop在tick之前被调用，那么isDone将为true，我们不应该再做任何事情
+        if (!this._isDone && this._elapsedTime > this._timeInSeconds){
+            this._elapsedTime -= this._timeInSeconds;
+            this._onTime(this);
+
+            if (!this._isDone && !this._repeats)
+                this._isDone = true;
+        }
+
+        this._elapsedTime += Time.deltaTime;
+
+        return this._isDone;
+    }
+
+    public initialize(timeInsSeconds: number, repeats: boolean, context: any, onTime: (timer: ITimer)=>void){
+        this._timeInSeconds = timeInsSeconds;
+        this._repeats = repeats;
+        this.context = context;
+        this._onTime = onTime.bind(context);
+    }
+
+    /**
+     * 空出对象引用，以便在js需要时GC可以清理它们的引用
+     */
+    public unload(){
+        this.context = null;
+        this._onTime = null as any;
+    }
+}