WARNING
Months are written in french.
Sort files in folders based on year and month of the mtime (modification time) of the file OR based on the date (YYYYMMDD) in the file name.
All the files should be in the very same folder.
node index.js mtype <pathofmyfiles>
node index.js namedate <pathofmyfiles>
+-- 2019-january.file
+-- 2018-october.file
+-- 2018-september.file
+-- 2019
| +-- january
| | +-- 2019-januray.file
+-- 2018
| +-- october
| | +-- 2018-october.file
| +-- september
| | +-- 2018-september.file