Weapon start

Started working on weapons.

+ added USP weapon
    - added materials
+ added Weapon.cs script
    - Implemented shooting
+ added WeaponSwitch.cs script
+ added WeaponHolder
+ added particles (muzzleflash, muzzlesmoke)
+ added additional camera for weapon clipping

Assets/Scripts/Weapons/WeaponSwitch.cs

@@ -0,0 +1,20 @@
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class WeaponSwitch : MonoBehaviour
+{
+
+    // Start is called before the first frame update
+    void Start()
+    {
+        
+    }
+
+    // Update is called once per frame
+    void Update()
+    {
+
+    }
+
+}