Allow searching for orders based on Accession Number and Order Number

We need to be able to search for orders based on their underlying accession number and order number

To do this, we should expand the OrderSearchCriteria to include accession number and order number parameters.

Then the underlying DAO method should be improved to search/filter on these parameters if present.

Note that since these are identification numbers, we only need to perform "Exact" matches.

This functionality will need to be backported to 2.3.x.