Task: List v2: Implement hashed key

[ashit-rath]

In list v2 every row has to be identified by a unique key, the key can by any unique value on the list data.

If no key is selected then the whole list data item has to be hashed using non-cryprographic algorithm (for fastest hash generation) to generate unique keys for each row.

A warning also should be added to the property depicting the importance of the property.