Add dependency to the new SDK
FileStore implementation

Not sure whether it is possible to obtain the available space from the API.
Todo...
Start and write the FileSystemDriver v2
New BoxFileInputStream

Wrapper over a Box API download request using a pipe, since the only option you
have is to provide the request with an OutputStream.
BoxFileInputStream: code changes
BoxFileInputStream: do pass the OutputStream as an argument

We need to connect it...
BoxFileSystemDriverV2: implement .newInputStream()
Create BoxFileOutputStream
More code in driver
More code for the driver...

Far from being optimal.
Complete first version of v2 driver
Code modifications
Depend on -base's latest HEAD
BoxBasicFileAttributesProvider: also provide mtime and ctime

Not sure that it has atime