Fixes #79, #80: extra check for setting writable dir in init
Fixes #79, #80: extra check for setting writable dir in init

fredyns/yii2-boilerplate,erycamel/yii2-app-advanced,yiisoft/yii2-app-advanced,dmitry-kulikov/yii2-app-advanced,vitezmiklos/test,AnTAVR/yii2-app-advanced-ru,Somefive/Athena,yiijan/yii2-app-advanced,jgege/MonApp,Somefive/Athena,mobilejazz/yii2-mj-cms-example,AnTAVR/yii2-app-advanced-ru,cophiel/YII2-Learning,cophiel/YII2-Learning,dixonsatit/yii2-dixon-starter,jgege/MonApp,yiijan/yii2-app-advanced,githubjeka/yii2-app-advanced,subdee/myportugal,mobilejazz/yii2-mj-cms-example,dixonsatit/yii2-dixon-starter,jacmoe/yii2-app-advanced-zurbified,githubjeka/yii2-app-advanced,nikbas/yii2-app-advanced,AnTAVR/yii2-app-advanced-ru,fredyns/yii2-boilerplate,fredyns/yii2-boilerplate,tibrus/yii2-app-advanced,yiisoft/yii2-app-advanced,subdee/myportugal,OneServices/OneCMS,hiqsol/yii2-app-advanced,erycamel/yii2-app-advanced,dmitry-kulikov/yii2-app-advanced,jacmoe/yii2-app-advanced-zurbified,nikbas/yii2-app-advanced,urmaul/yii2-app-advanced-mongodb