Support passing expectedNumSlivers into v1/v2 subtest_DeleteSlivers().
Support passing expectedNumSlivers into v1/v2 subtest_DeleteSlivers().

plantigrade/geni-tools,plantigrade/geni-tools,tcmitchell/geni-tools,ahelsing/geni-tools,ahelsing/geni-tools,tcmitchell/geni-tools