重构Resource的Asset模块，主要为BundleAssetHelper,支持同步异步资源加载

Author: wanderer

GameFramework/Runtime/Audio/AudioManager.cs

@@ -271,7 +271,7 @@ private AudioClip GetAudioClip(string assetName)
 			AudioClip audioClip = null;
 			if (!_audioClipSources.TryGetValue(assetName, out audioClip))
 			{
-				audioClip = _resourceManager.LoadAssetSync<AudioClip>(assetName);
+				audioClip = _resourceManager.Asset.LoadAsset<AudioClip>(assetName);
 				_audioClipSources.Add(assetName, audioClip);
 			}
 			return audioClip;

GameFramework/Runtime/DataTable/DataTableManager.cs

@@ -44,7 +44,7 @@ public void LoadDataTable(string dataTablePath,Action<bool,string, IDataTable> c
                 return;
             }
             //DataTable解析
-            _resource.LoadAsset<TextAsset>(dataTablePath,(data) =>
+            _resource.Asset.LoadAsset<TextAsset>(dataTablePath,(data) =>
             {
                 bool result = false;
                 IDataTable iDataTable = null;
@@ -66,7 +66,7 @@ public void LoadDataTable(string dataTablePath,Action<bool,string, IDataTable> c
                 //加载DataTable的回调
                 callback?.Invoke(result, dataTablePath, iDataTable);
                 //去掉文本的引用计数
-                _resource.UnloadAsset(dataTablePath);
+                _resource.Asset.UnloadAsset(dataTablePath);
             });