patched histology blocks worklist to hide non-block/slide sample types; 1 new & 1 renamed field for genomics, returned additional_samples to SpecimensBlood for legacy ppm xml validation
adapted Genomics registration to enable select button if patient exists but no attached request - previously was blocked if patient registered and request not subsequently submitted
fixed RDBO error msg if sample_linkage_form select submitted empty; put xml validation into genomics_xml.pl with admin notification of failure; added validation tests to genomics.t
