* Freenas zpool improvement
Don't try to multiply two strings (cast units to int)
No need to double fetch database entries to check if it exists.
Only poll zpoolUsed to speed up polling
* Block zpool usage on new devices, they dropped support.
TRUENAS-MIB included for reference
* Fix polling, update test data
It's also possible to do zpool IO from the MIB, but diskIO on
LibreNMS makes a lot of assumptions about it coming from the UCD
MIB.
This changeset adds detection for FreeNAS and TrueNAS - despite
having their own enterprise number, the snmpd uses the FreeBSD
one.
The naming is a bit all over the place, because this reflects
reality - IXSystems produce FreeNAS and TrueNAS, the product lines
have merged to eliminate FreeNAS, but TrueNAS still calls itself
FreeNAS everywhere except the GUI.
