implicitly define the keys name when the configured value is empty
implicitly define the keys name when the configured value is empty

WouterJ/phpcr-odm,WouterJ/phpcr-odm,valiton-forks/phpcr-odm,valiton-forks/phpcr-odm,Ocramius/phpcr-odm,Ocramius/phpcr-odm,sarcher/phpcr-odm,doctrine/phpcr-odm,sarcher/phpcr-odm,uwej711/phpcr-odm,AxaliaN/phpcr-odm2,uwej711/phpcr-odm,AxaliaN/phpcr-odm2,doctrine/phpcr-odm