Provides a struct to hold usage data.
##Examples
iex> u = %UsageStat{path: "/", used_persent: "14"} ...> u.path "/"
t() :: %Facts.Disk.UsageStat{free: float, fs_type: binary, inodes_free: float, inodes_total: float, inodes_used: float, inodes_used_percent: float, path: binary, total: float, used: float, used_percent: float}