adding download copies functionnality
manage only finished drops
manage case where no copies are availables
adding between date download code
adding views for downloading drops during period
debug download drops by date
correct the case where begin and end date are the same.
( full day  start at 0h00 and end at 23:59 )  so we should be able to have the same day on begin and end day.
changing the folder name  when the drop is finished ( adding the datetime in the name )
correct EN traduction (totalGrade)
Merge pull request #117 from iCAPLyon1/download_copies

Download copies