Add calculation of Prayer Points obtained / h

[yuriks]

It's already possible to calculate this using the drop rate of bones, but this needs to be done separately for each kind of bone, which makes picking the optimal PP/hr farming monster more difficult than it would otherwise be. It would be handy to enable the simulator to calculate and display this directly. (Possibly as an option in the loot tab to convert bones to PP, which would get subtracted from the PP usage by active prayers, giving you a negative PP/hr rate if you're having a net gain of PP.)

[wzurborg]

This would be a very helpful enhancement!