[ADDED] Hashrate modifier name and value

* [ADDED] Hashrate modifier value to getnavbardata
* [ADDED] Hashrate modifier name to getnavbardata

Fixes #1845 once merged.
[FIX] Apply proper fee on auto-payouts

Thanks IRC blonkel for the heads up.
[IMPROVED] Deduct TXFEE in Transaction CreateDebit

No need to deduct the fees on our cronjob, do it automatically in our
transaction class when creating a Debit record.