HPCC-8882 Add a dependency from thorhelper to dalibase

Strangely the system linked on linux even though there was a dependency.

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>
HPCC-8882 Add const to some addCluster() arguments

Cleaned up while investigating the dalibase dependency.

Signed-off-by: Gavin Halliday <gavin.halliday@lexisnexis.com>