playlists now save to files, can be restored from files

frontend/wailsjs/go/frontendutil/FrontendUtil.d.ts

@@ -4,4 +4,6 @@ import {context} from '../models';
 
 export function DirectoryPicker():Promise<string>;
 
+export function PlaylistFilePicker():Promise<string>;
+
 export function SetContext(arg1:context.Context):Promise<void>;

frontend/wailsjs/go/frontendutil/FrontendUtil.js

@@ -6,6 +6,10 @@ export function DirectoryPicker() {
   return window['go']['frontendutil']['FrontendUtil']['DirectoryPicker']();
 }
 
+export function PlaylistFilePicker() {
+  return window['go']['frontendutil']['FrontendUtil']['PlaylistFilePicker']();
+}
+
 export function SetContext(arg1) {
   return window['go']['frontendutil']['FrontendUtil']['SetContext'](arg1);
 }