PDI-11979 - Junits tests

Added junit test based on load/save framework.
PDI-11979 - Fieldnames in the "Execution results" tab of the Job executor step saved incorrectly in repository

added simple fix to loadRepository method.
Merge pull request #473 from prakapenka/PDI-11979

PDI-11979 - Fieldnames in the "Execution results" tab of the Job executor step saved incorrectly in repository