HPCC-8563 - Ensure groups/clusters are consistently lowercased.

Some places already ensured that groups and cluster names were
lower cased. A number of places didn't inparticular, adding a
cluster name to a logical name, which caused some erroneous
mismatching if the config had mixed cased and published files
didn't

Signed-off-by: Jake Smith <jake.smith@lexisnexis.com>
Merge pull request #3867 from jakesmith/hpcc-8563

HPCC-8563 - Ensure groups/clusters are consistently lowercased.

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>