Add a sheet with Meta information to the XLSX output

[berntpopp]

For reproducibility it would be helpful to add meta information to the Excel output including filter setting and column documentation.

[berntpopp]

Investigate option to also do this for TSV output but stiull keep a valid output (e.g. comments)

[berntpopp]

Changes to tsv_to_excel.R will be required for implementation.

• Include an argument to set the sheet name.
• Instead of overwriting, add an argument to add the sheet to an existing excel file.
• Add logic to not overwrite existing sheets with the same name if they already exist, but instead add a number as an iterator.

Implementation in #10