Space values are always reported as 0

[janseeger]

free space is always reported as 0 in root summary.

[janseeger]

https://github.com/waldheinz/fat32-lib/blob/master/src/main/java/de/waldheinz/fs/fat/FatFileSystem.java#L252

[janseeger]

http://www.c-jump.com/CIS24/Slides/FAT/F01_0070_unallocated.htm

[janseeger]

also affects the total space.

[janseeger]

waiting on waldheinz/fat32-lib#23