implement show copyright info on album page

+ rewrite server track and album models to use destructuring

src/interfaces.ts

@@ -17,6 +17,7 @@ export interface Track {
   discnumber?: number;
   index?: number;
   uniq_hash: string;
+  copyright?: string;
 }
 
 export interface Folder {
@@ -40,6 +41,7 @@ export interface AlbumInfo {
   is_single: boolean;
   hash: string;
   colors: string[];
+  copyright?: string;
 }
 
 export interface Artist {
@@ -108,5 +110,3 @@ export interface FetchProps {
   put?: boolean;
   headers?: {};
 }
-
-