Feat: ImageRequestInit (#979)

* add ImageRequestInit & fix Hako

* remove multisrc fetchFile

* remove plugins fetchFile

* update docs and template file

plugins/chinese/69shu.ts

@@ -180,8 +180,6 @@ class Shu69 implements Plugin.PluginBase {
     return novels;
   }
 
-  fetchImage = fetchFile;
-
   filters = {
     rank: {
       label: '排行榜',

plugins/chinese/69xinshu.ts

@@ -181,8 +181,6 @@ class XinShu69 implements Plugin.PluginBase {
     return novels;
   }
 
-  fetchImage = fetchFile;
-
   filters = {
     class: {
       label: '分类',

plugins/chinese/linovelib.ts

@@ -521,13 +521,6 @@ class Linovelib implements Plugin.PluginBase {
     return novels;
   }
 
-  async fetchImage(url: string): Promise<string | undefined> {
-    const headers = new Headers({
-      'Referer': `${this.site}/`,
-    });
-    return await fetchFile(url, { headers });
-  }
-
   filters = {
     rank: {
       label: '排行榜',