Allow hash to be null in log INFO when closing table
Only close table if it hasn't already been closed
Retrieve group details at initialisation if not provided
Only update OriginalFile if table was modified.

modified flag added to HdfStorage, TableI.close() checks this flag
Use try-finally to ensure writes are always flushed
Forgot to commit the debug log message
Mock QueryService.get, Add details.group to OriginalFile
Add test to check unloaded OriginalFile is automatically loaded
Merge pull request #1807 from manics/tables_group_log-11697

Cleanup TableI.close() #11697