add ensure method. do not create nested models arrays.
add ensure method. do not create nested models arrays.

staabm/Payum,StoreFactory/Payum,formapro-forks/Payum,formapro-forks/Payum,Payum/Payum,StoreFactory/Payum,ASKozienko/Payum,Payum/Payum,aitboudad/Payum,StoreFactory/Payum,fullpipe/Payum,digisec/Payum,digisec/Payum,fullpipe/Payum