[TENE-396] Adding next processing step to the records-processor and new plugins mechanism

Added next processing step in the record processor. Now just before writing to the database, the postprocessing is called. The postprocessing is based on the given sequence in app-properties. At the moment there are only test plugins, so postprocess.chain-sequence: is empty. The program accepts both the complete absence of this property and an empty value.

If postprocessing encounters an error, the original record is written to the database, while if the call chain passes without any exceptions, the updated record goes to the database.

Closes TENE-396