[hyper zerk] make it cancelable with reg attacks

I have been doing Aufheben with a DK and they where theorising risk rewarding techs involving hyper zerking.
I was thinking about giving hyper zerk the same treatment as Darksight and barrel where they can break out of that status with the press of regular attack button.
The current cancelling method is by right clicking the buff.

I think this would allow DKs to integrate hyperzerking in a more safe or aggressive way depending of the situation comming.

Pro : avoid grabing mouse to point and clic hyper zeer to cancel it. Making the learning curve a bit less steep.

Cons : if trying to cancel during an ongoing animation it would likely not get registered by the game and it's not possible to put on macro to buffer it