fix #78 change to count-limited split for df output to account for space...

...s in mountpoints
Regex.Split() allows you to stop splitting at n, in this case 6. strings.Split has no equivalent way to stop at n-splits that I could find in godoc.

So when given a line such as this on \s+ for the delim:
/dev/loop1                    61671424    61671424            0     100% /home/nextraztus/test/Mount With Spaces

You get:
[/dev/loop1][61671424][61671424][0][100%][/home/nextraztus/test/Mount With Spaces]

Instead of
[/dev/loop1][61671424][61671424][0][100%][/home/nextraztus/test/Mount][With][Spaces]