Added some validation specs for Row::put
Implemented specs validating Row::put

Row::put raises an exception of :block is not include

Row::put raises an error if :into is not included

Row::put raises an error if :index is not included

Cleaned up the put validation just a little bit
Added some validation specs for Row::slot_full?
Implemented specs testing validation of Row::slot_full?

Row::slot_full? raises an error if :index option not included

Row::slot_full? raises error if :in option not included