A new version for 2024:
- bugfix in destination file grid LD outputs
- adds sb object methods to aggregate data from multiple runs, then save asc files from the aggregated data, with usage in main for allages example
- adds a second function to run the tool, with this one using the origin file header to obtain all the age groups and then run each one in turn
- change default files to save, add exta all and total asc outputs
- iteritems deprecated in Pandas, alias it to items