addded 3 and 4 players support.

Assets/Resources/Levels.xml

@@ -4,7 +4,8 @@
   <Level>
     <Item prefab="Start_Position" x="5" />
     <Item prefab="Start_Position" x="-5" />
-    <Item prefab="Start_Position" />
+    <Item prefab="Start_Position" x="-2.5" />
+    <Item prefab="Start_Position" x="2.5" />
     <Item prefab="ground" y="-1.5" scalex="22.78" />
     <Item prefab="ground" x="-7.5" y="-0.38" rot="90" scalex="30" />
     <Item prefab="ground" x="7.5" y="-0.38" rot="90" scalex="30" />

Assets/Resources/Prefabs/Player Four.prefab.meta

+fileFormatVersion: 2
+guid: 87c914bf4d2b95445a1629a988e459a2
+timeCreated: 1433522108
+licenseType: Free
+NativeFormatImporter:
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Resources/Prefabs/Player Three.prefab.meta

+fileFormatVersion: 2
+guid: c00165c178f108e4b876b116c91b7768
+timeCreated: 1433522066
+licenseType: Free
+NativeFormatImporter:
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Scripts/PlayerControl.cs

@@ -157,7 +157,6 @@ public class PlayerControl : MonoBehaviour
         }
 
         //finally set the velocity:
-        Debug.Log(velocity.y);
         body2D.velocity = velocity + currentPushSpeed;
     }