Added ultrakillstyle_freshnessenable and ultrakillstyle_freshnessmultiplier ConVars

Fixed shooting related bug

Make code neater
This time 100% fixed problem with mighty foot engage

Now actually fixed bug with arms decreasing freshness

Fixed arms using weapon freshness
Other small stuff

Added Headshot Combo and Ricoshet style
Some changes to style meter
Fixed (i think) error when 3D Particle System is not installed

Small code change

Fixed Instakill stye bonus not showing up

Fixed problem with Mighty foot
Added new style bonus

Fixed style bonus for vehicle to not pop up
Crossbow now decreases freshness multiplier more slow
Fixed bug