Support more types of hits

[PsychicMuffin]

We should support hits of elemental types at the very least, but we should probably include flags for isDot, isSpell, and isReflect, which would be off by default. This would be relatively trivial to add to the calculations and modifiers, but would be complex to add from the UI perspective.

[eps1lon]

Does this also include "deal extra Damage as X Element".

Currently you have to tinker with the damage shifts option which changes every time you would add another "extra Damage" mod.

[ficocelliguy]

We were thinking about that in terms of a monster buff, there's an issue for supporting map mods (#71). But yes, that's an important feature to cover.