Bug 3 fixed.

What was the root cause of the bug?
arrayForFetchRequestWithName function was not using any sort descriptors to sort the data as needed.

How did you fix the problem?
The desired output required AllModels to be sorted by first owner.ownerName then by modelId. Also in order to print the model with required formatting description function is added to ModelsEntity class. During this bug ViewController.m is required not to be changed so changes are done in arrayForFetchRequestWithName function. Also a more generic function named arrayForFetchRequestWithName:andSortDescriptors is added.