fix broken ref (#233)

* fix broken ref for en

* fix broken ref for zh

docs/en/manuals/extensions.md

@@ -64,10 +64,10 @@ To create a new extension, create a folder in the project root. This folder will
 
 The optional *manifests* folder of an extension contains additional files used in the build and bundling process. Files should be placed in subfolders named by `platform`:
 
-* `android` - This folder accepts a manifest stub file to be merged into the main application ([as described here](extensions-manifest-merge-tool)). The folder can also contain a `build.gradle` file with dependencies to be resolved by Gradle ([example](https://github.com/defold/extension-facebook/blob/master/facebook/manifests/android/build.gradle)). Finally the folder can also contain zero or more ProGuard files (experimental).
-* `ios` - This folder accepts a manifest stub file to be merged into the main application ([as described here](extensions-manifest-merge-tool)).
-* `osx` - This folder accepts a manifest stub file to be merged into the main application ([as described here](extensions-manifest-merge-tool)).
-* `web` - This folder accepts a manifest stub file to be merged into the main application ([as described here](extensions-manifest-merge-tool)).
+* `android` - This folder accepts a manifest stub file to be merged into the main application ([as described here](/manuals/extensions-manifest-merge-tool)). The folder can also contain a `build.gradle` file with dependencies to be resolved by Gradle ([example](https://github.com/defold/extension-facebook/blob/master/facebook/manifests/android/build.gradle)). Finally the folder can also contain zero or more ProGuard files (experimental).
+* `ios` - This folder accepts a manifest stub file to be merged into the main application ([as described here](/manuals/extensions-manifest-merge-tool)).
+* `osx` - This folder accepts a manifest stub file to be merged into the main application ([as described here](/manuals/extensions-manifest-merge-tool)).
+* `web` - This folder accepts a manifest stub file to be merged into the main application ([as described here](/manuals/extensions-manifest-merge-tool)).
 
 
 ## Sharing an extension

docs/zh/manuals/extensions.md

@@ -64,10 +64,10 @@ Defold 提供了一个云端服务器编译方案. 游戏项目的各种依赖,
 
 *manifests* 包含编译时不同平台所需的配置文件. 配置文件要根据称为 `platform` 的子文件夹分类放置:
 
-* `android` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](extensions-manifest-merge-tool)). 还可以存放 `build.gradle` 文件及其依赖以便 Gradle 可以解析 ([示例](https://github.com/defold/extension-facebook/blob/master/facebook/manifests/android/build.gradle)). 还能存放0个或多个 ProGuard 代码混淆文件 (试验功能).
-* `ios` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](extensions-manifest-merge-tool)).
-* `osx` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](extensions-manifest-merge-tool)).
-* `web` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](extensions-manifest-merge-tool)).
+* `android` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](/manuals/extensions-manifest-merge-tool)). 还可以存放 `build.gradle` 文件及其依赖以便 Gradle 可以解析 ([示例](https://github.com/defold/extension-facebook/blob/master/facebook/manifests/android/build.gradle)). 还能存放0个或多个 ProGuard 代码混淆文件 (试验功能).
+* `ios` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](/manuals/extensions-manifest-merge-tool)).
+* `osx` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](/manuals/extensions-manifest-merge-tool)).
+* `web` - 这里存放片段配置文件用以与主配置文件混合 ([就像这里介绍的那样](/manuals/extensions-manifest-merge-tool)).
 
 
 ## 共享原生扩展
@@ -282,4 +282,4 @@ platforms:
 * [iOS 和 Android 的内支付扩展程序](https://github.com/defold/extension-iap)
 * [iOS 和 Android 的 Firebase Analytics 扩展程序](https://github.com/defold/extension-firebase-analytics)
 
-[Defold 资源中心](https://www.defold.com/assets/) 也包含有许多原生扩展项目资源.
+[Defold 资源中心](https://www.defold.com/assets/) 也包含有许多原生扩展项目资源.