HPCC-9544 ecl-packagemap-add should report unresolved files

ecl-packagemap-add listing the files it could not locate would
allow this type of packagemap issue to be resolved much more
quickly and no longer one at a time.

Signed-off-by: Anthony Fishbeck <Anthony.Fishbeck@lexisnexis.com>
Merge pull request #4540 from afishbeck/packagemapAddFilesNotFound9544

HPCC-9544 ecl-packagemap-add should report unresolved files

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>