changed PrepareConfiguration class -- refactoring
changed PrepareConfiguration class -- deleted unused fields
changed PrepareConfiguration class -- refined setOutputDirName()
changed file reader classes -- implemented file writer for outputing error records
changed PrepareConfiguration class -- refined setErrorRecordOutputDirName()
changed file reader classes -- refactoring
changed FileReader class -- added setErrorRecordsOutputStream() for unit testing
changed bin/td-bulk-import -- refactoring
minor change of bin/td-bulk-import
minor change of bin/td-bulk-import v2
changed Constants class -- deleted unncessary TODO comments
changed CSVPrepareConfiguration class -- deleted unnecessary fields