Backstab & Back hit damage implemented (But not updated yet)

As mentioned before, the ghost will be boosted by a special backstab one-hit kill ability, this is working properly now. Backstab will one-hit-kill a player and half the suspicious mark time. 

• Added a 50% extra damage for shooting the backside of the player. This value might be further adjusted in the future. 

• Added a height detect function to snap all health bars right above players' heads no matter the height of the avatar. 

• Network structure overhaul to stabilize gameplay procedure. Now it should be much more reliable than in the close beta version.

• Renamed "Corruption" into "Suspicious" stage for easier reading.

The quest build is updated to the weekend beta version, but I'm going to hold the update until I got the other main issues solved.