Simplify & consolidate DPR calculations

[vigo2]

There's quite a bit of complexity to support the DPR mode for all abilities, and I believe the resulting DPR values aren't any more meaningful than those calculated by simpler methods:

a) statistical calculation, essentially average damage / average rage cost. For HS, Cleave, and Slam, this typically includes the hidden rage and damage costs of lost MH swing time, and the rage and damage gains from a queued OH swing. Execute also needs additional averaging. Most procs or external buffs are ignored.

b) sim with auto attacks only, and calculate damage (d0), rage gained (rg0), and rage spent (rs0); then, to find a "second order" DPR value for an ability, sim again with only auto attacks and that ability enabled, calculating damage (d), rage gained (rg), and rage spent (rs). DPR value is (d - d0) / ((rg - rs) - (rg0 - rs0)). It includes all procs or external buffs, e.g. higher Flurry uptime, extra attacks, Deep Wound damage.

I'm actually leaning towards a), since that's already enough to establish ability priorities, which is - as far as I know - the primary use of the DPR metric. Having those values upfront might also - one day ;) - allow to cut down the rotation configuration.