Add french language (#460)

* Create fr.json

* Update index.js

* Update i18n.d.ts

* Update option.md

* Update option.md

* Update artplayer.d.ts

docs/assets/ts/artplayer.d.ts

@@ -401,7 +401,7 @@ export type Events = {
     restart: [];
 };
 
-type I18nKeys = 'en' | 'zh-cn' | 'zh-tw' | 'pl' | 'cs' | 'es' | 'fa' | (string & Record<never, never>);
+type I18nKeys = 'en' | 'zh-cn' | 'zh-tw' | 'pl' | 'cs' | 'es' | 'fa' | 'fr' | (string & Record<never, never>);
 
 type I18nValue = {
     'Video Info': string;
@@ -1059,4 +1059,4 @@ export type Utils = {
     escape(str: string): string;
     capitalize(str: string): string;
     isStringOrNumber(val: any): boolean;
-};
+};