Clean up and revise StartAttack()

[kphoenix137]

Removes the logic that mimics the Hellfire oversight that resulted in mixing faster attack speeds giving undesirable or confusing results. Reduces amount of lines in code maintaining vanilla Diablo logic.

[kphoenix137]

I believe it would be quite interesting to modify dual wielding behavior by adding frame skips together, capping them at 4 for including first frame and 3 for not including first frame, in order to make it more logical and appealing, however that kind of change may be entirely out of scope.

[obligaron]

I'm fine with it after clang fix. 🙂