Added the assign assoc methods for data product
fixed one
Added testing to make sure that the associated stream is deleted after the data product is retired
Merge branch 'master' into clean_up_stream_for_data_product
well, enhanced resource registry does the assigning dynamically.
Merge pull request #839 from swarbhanu/clean_up_stream_for_data_product

Fix memory leak related to stream associated with data product that is left around