Return non-zero values for Statfs call
Return non-zero values for Statfs call

This fixes the problem where Finder thinks there
isn't enough free space to copy files.

This closes #415. This closes #413.

keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/client,keybase/kbfs,keybase/client,keybase/kbfs,keybase/client,keybase/kbfs,keybase/kbfs,keybase/client,keybase/client,keybase/client,keybase/client