AKS74U instead of MP5 for CSS

AKS74U to replace the old MP5 model! This is a completely redesigned model with new animation textures, as well as improved sounds. The model works perfectly on v34 and later versions of the game. Authors: Model:Millenia Animation:4Echo Textures:BuLL5H1T Sounds:Magmacow,NightmareMutant Have fun with the new model! P.S. If you want to see more brand new models with global changes, don't forget to thank me.