Remove datastructure documentation from 4.5

As per conversation with Matt Ingenthron - we want to remove all documentation for datastructures from the 4.5 documentation now that 4.6 has been released.

Tony Hillman would you mind doing this?
You will have to remove the datastructure entry from each of the language's ditamap and then also delete the 'datastructures.dita' from each language's subfolder.