Don't use colors anymore to detect end of labels: Now detect presence of date in first cell.
Dont't fail when a "values" row contains an empty line, but ignore line.
Cleanup code (using flake8).
Remove data files that must not be in project source.
Small adjustments of the code + new files
Improve detection of cell formats.
Improve detection of dates. Convert FRF to €. Improve logging.
Add xls files. Rename files with diacrital characters and CSV files.