Fixes #1643: Added default value for `Captcha::options`
Fixes #1643: Added default value for `Captcha::options`


OrlandoST/instapro,OrlandoST/yii2-app-basic,IngridMendes/boigalera,IngridMendes/boigalera,githubjeka/yii2-app-basic,IngridMendes/boigalera,jacmoe/yii2-app-basic-zurbified,yiisoft/yii2-app-basic,matperez/yii2-app-basic-with-environments,andreybolonin/yii2-app-basic,karoldanutama/dev-ops-yii2-app-basic,tigokr/intermedia_test_0,callmez/yii2-app-wechat,marianturchyn/yii2-app-basic,AdeAttwood/Yii2-Basic-Grunt,jarioneto/yii2-app-rest,fredyns/shippingweight,CanDo-com/yii2-app-basic,AdeAttwood/Yii2-Basic-Grunt,OrlandoST/instapro,krissss/yundou,yiisoft/yii2-app-basic,adiferd/dev-ops-yii2-app-basic,DawidMyslak/home-budget,fredyns/shippingweight,Vitashev/yii2-app-basic,jacmoe/yii2-app-basic-zurbified,AdeAttwood/Yii2-Basic-Grunt,pana1990/yii2-app-basic,DawidMyslak/home-budget,themccallister/yii2-app-basic,githubjeka/yii2-app-basic,wartron/yii2-app-basic-account,CanDo-com/yii2-app-basic,dasscheman/yii2-app-basic,dasscheman/yii2-app-basic,novomirskoy/yii2gallery,cbn052293/Test_Yii,novomirskoy/yii2gallery,OrlandoST/yii2-app-basic,tiagocardosos/yii2-sample-app-urlshortener-mongo,matperez/yii2-app-basic-with-environments,tird/yii2-app-basic,alfredleo/yii2-app-basic,tigokr/intermedia_test_0,aerios/dev-ops-yii2-app-basic,wojtonow/yii2-basic,wojtonow/yii2-basic,hanupas/dev-ops-yii2-app-basic