Create reusable Synology proxy

- Migrate DiskStation and DownloadStation to use new proxy
- Move DiskStation proxy UI logic into component

src/widgets/diskstation/widget.js

@@ -1,7 +1,27 @@
-import synologyProxyHandler from "./proxy";
+import synologyProxyHandler from '../../utils/proxy/handlers/synology'
 
 const widget = {
+  // cgiPath and maxVersion are discovered at runtime, don't supply
+  api: "{url}/webapi/{cgiPath}?api={apiName}&version={maxVersion}&method={apiMethod}",
   proxyHandler: synologyProxyHandler,
+
+  mappings: {
+    "system_storage": {
+      apiName: "SYNO.Core.System",
+      apiMethod: "info&type=\"storage\"",
+      endpoint: "system_storage"
+    },
+    "system_info": {
+      apiName: "SYNO.Core.System",
+      apiMethod: "info",
+      endpoint: "system_info"
+    },
+    "utilization": {
+      apiName: "SYNO.Core.System.Utilization",
+      apiMethod: "get",
+      endpoint: "utilization"
+    }
+  },
 };
 
 export default widget;