Added FreeBSD zfs support per #1063. (#1394)
Added FreeBSD zfs support per #1063. (#1394)

Based on the solaris implementation.  There's a lot of other sysctls
available on FreeBSD that aren't reported here.  It'll be easy to add,
if they're useful.  All of the sysctls are uint64.

Signed-off-by: Derek Marcotte <2b34ee4d709d87a8c0ead0c7f448bdaacb6f7d31@razorfever.net>
prometheus/node_exporter,prometheus/node_exporter,siavashs/node_exporter,siavashs/node_exporter,prometheus/node_exporter,siavashs/node_exporter,siavashs/node_exporter