The function creates a folder (only once) and then controls files that need to be downloaded and placed in this folder.
cacheManager(nameFile)
the name of the file or folder
the path to the file we need
The localisation of the folder is defined in the `.Renviron` file, by setting the `OSMOSE_DIR` environment variable: - On Linux/Mac Os X : `OSMOSE_DIR=/Users/Nicolas/Desktop/OSMOSE_TEST/R` - On Windows: `OSMOSE_DIR=C:\Users\Nicolas\Desktop\OSMOSE_TEST\R`
If this variable is not set, the files will be downloaded into a temporary directory.