#499 Downlaodmodul should handle multiple organizations in 1 installation

[Markus Fassbender]

If you have multiple organizations than you can't handle it in the download module. This module can only handle 1 organization per installation.

To handle more organizations there must be several sub folders in adm_my_files/download. Maybe we should add a folder for every organization with the id.
e.g.:
adm_my_files/download/1/
adm_my_files/download/2/
adm_my_files/download/3/
...