Merge with Stun

I suggest we merge this page with Stun (and maybe also Types of Hits) to Combat System

They're very closely related since they're both what happen after an attack, and especially since knockdown is controlled by both systems(KD timer controls when it happens, stun time controls the distance).

Also, having both on the same page should make it easier to explain the difference between the two (The charts at the bottom of both pages look similar, so someone viewing one after the other may assume it's the page they already read).

Any objections?

Will start next week.